Iohexol is an iodinated nonionic, low-osmolar contrast medium used for visualization during angiography and excretory urography. Iohexol is used to enhance computed tomography head and body imaging and to investigate the presence of cerebral infarctions, active infections, arteriovenous malformations, aneurysms and lesions or tumors (both malignant and nonneoplastic) in the liver, kidneys, pancreas, aorta, abdominal cavity, pelvis, retroperitoneal space, and the mediastinum. Iohexol can be used orally for radiographic examinations of the gastrointestinal tract and is particularly useful for this indication when barium is contraindicated. Iohexol can be administered into joints for arthrography and into body cavities for visualization of the uterus, fallopian tubes, peritoneum, and bladder. In addition, iohexol can be administered intrathecally for use during myelography and to enhance myelographic computed tomography imaging. Iohexol was approved by the FDA on December 26, 1985.
Iodinated contrast media can be classified as either ionic or nonionic and high-osmolar or low-osmolar. In general, ionic contrast media (diatrizoate and iothalamate) have a high osmolality (1400 mOsm/kg water or higher) when compared to plasma (285 mOsm/kg water) and cerebrospinal fluid (301 mOsm/kg water). One ionic agent, ioxaglate, is considered to be low-osmolar with an osmolality of 600 mOsm/kg water. Nonionic contrast media such as iopamidol, iohexol, iopromide, and ioversol are considered low-osmolar with osmolalities ranging from approximately 600 mOsm/kg water to 900 mOsm/kg water. Iodixanol, a nonionic contrast medium, is considered to be iso-osmolar with an osmolality of 290 mOsm/kg water. Because one of the properties related to toxicity and adverse events is the osmolality of the contrast media, ionic contrast media tend to be associated with more adverse events than nonionic. Less toxicity is reported with the low-osmolar ionic contrast media ioxaglate than high-osmolar contrast media; however, the incidence of adverse events is slightly higher with ioxaglate when compared to low-osmolar nonionic contrast media. In addition, recent, limited data indicate that iodixanol, the iso-osmolar contrast medium, may be associated with even less toxicity than low-osmolar media. Radiopaque efficacy of the contrast media depend on the amount of iodine administered to the patient and there appears to be no major difference in the efficacy of the various agents when equal amounts of iodine are given.
Overall, most people tolerate contrast media injections without adverse reactions. However, severe, life-threatening reactions do occur. Acute renal failure can occur in up to 50% of patients with risk factors (i.e., renal insufficiency, diabetes mellitus, dehydration etc.). Using the smallest volume and concentration of nonionic contrast media and adequate hydration before and after the procedure or exam is recommended to minimize the risk of nephrotoxicity. Hypersensitivity reactions can occur in up to 15% of patients and tend to be more common with the use of ionic contrast media in at-risk patients (i.e., atopy, asthma, previous reaction to contrast media, etc.); anaphylaxis is rare (0.04-0.22% incidence). In patients with risk factors for hypersensitivity, the incidence and severity of reactions can be minimized with the use of nonionic contrast media and/or prophylactic corticosteroids plus antihistamines. Cardiovascular toxicity can occur but is more prevalent in coronary arteriography and with the use of ionic contrast media. Cardiovascular shock, unconsciousness and death occur very rarely; these life-threatening reactions are unpredictable; they can occur with any contrast media and are not related to the route of administration or patient risk factors. Major motor seizures are rare but have been associated with the use of contrast media; however, seizures are more commonly associated with intrathecal use. Prior to the administration of contrast media, patients should be evaluated for risk factors of toxicity. In those patients with risk factors, the benefits of the procedure or exam should be carefully evaluated and preventive measures should be taken when possible.
General Administration Information
For storage information, see specific product information within the How Supplied section.
-Patients should be well hydrated prior to and after iohexol injection administration. A suggested common regimen in eligible patients (e.g., those patients in which fluid administration would not be contraindicated) is 1 mL/kg/hour of 0.9% Sodium Chloride Injection starting at least 4 hours prior to and continuing for at least 12 hours after the procedure or exam.
-In patients with a history of allergic reaction to contrast media, those with a history of asthma or allergic reactions to drugs or foods, nonionic contrast media should be used. In addition, consider administering prednisone 50 mg PO (or equivalent dose of other steroids) 13 hours, 7 hours, and 1 hour prior to the exam or procedure plus diphenhydramine 50 mg IM/PO 1 hour prior to the procedure. The administration of prophylactic steroids and antihistamines does not prevent all hypersensitivity reactions, but reduces the likelihood and may decrease the severity of the reaction.
-Use the lowest dose necessary to obtain adequate visualization. Individualize the volume, strength, and rate of administration of iohexol injection. Consider factors such as age, body weight, vessel size, blood flow rate within the vessel, anticipated pathology, degree and extent of opacification required, structures or area to be examined, disease processes affecting the patient, and equipment and technique to be employed.
Route-Specific Administration
Oral Administration
Oral Liquid Formulations
-Administer oral dose all at once or over a period of up to 45 minutes if there is difficulty consuming the required volume.
-In patients receiving both oral and intravenous contrast, give the oral contrast first.-Adults: Administer intravenous dose up to 40 minutes after the oral dose.
-Pediatric patients: Administer intravenous dose up to 60 minutes after the oral dose.
-Commercially available as a 9 mg iodine/mL and 12 mg iodine/mL oral solution. Alternatively, intravenous formulations (i.e., Omnipaque 240, 300, 350) may be administered orally either undiluted or mixed with water, carbonated beverages, milk, infant formula, or juice.
-Dilutions of iohexol injection should be prepared just prior to use; discard the unused portion after the procedure.-To achieve 1,000 mL at a final concentration of iohexol 6 mg iodine/mL, add 25 mL of iohexol 240 mg iodine/mL (Omnipaque 240) to 975 mL of diluent.
-To achieve 1,000 mL at a final concentration of iohexol 6 mg iodine/mL, add 20 mL of iohexol 300 mg iodine/mL (Omnipaque 300) to 980 mL of diluent.
-To achieve 1,000 mL at a final concentration of iohexol 6 mg iodine/mL, add 17 mL of iohexol 350 mg iodine/mL (Omnipaque 350) to 983 mL of diluent.
-To achieve 1,000 mL at a final concentration of iohexol 9 mg iodine/mL, add 38 mL of iohexol 240 mg iodine/mL (Omnipaque 240) to 962 mL of diluent.
-To achieve 1,000 mL at a final concentration of iohexol 9 mg iodine/mL, add 30 mL of iohexol 300 mg iodine/mL (Omnipaque 300) to 970 mL of diluent.
-To achieve 1,000 mL at a final concentration of iohexol 9 mg iodine/mL, add 26 mL of iohexol 350 mg iodine/mL (Omnipaque 350) to 974 mL of diluent.
-To achieve 1,000 mL at a final concentration of iohexol 12 mg iodine/mL, add 50 mL of iohexol 240 mg iodine/mL (Omnipaque 240) to 950 mL of diluent.
-To achieve 1,000 mL at a final concentration of iohexol 12 mg iodine/mL, add 40 mL of iohexol 300 mg iodine/mL (Omnipaque 300) to 960 mL of diluent.
-To achieve 1,000 mL at a final concentration of iohexol 12 mg iodine/mL, add 35 mL of iohexol 350 mg iodine/mL (Omnipaque 350) to 965 mL of diluent.
-To achieve 1,000 mL at a final concentration of iohexol 15 mg iodine/mL, add 63 mL of iohexol 240 mg iodine/mL (Omnipaque 240) to 937 mL of diluent.
-To achieve 1,000 mL at a final concentration of iohexol 15 mg iodine/mL, add 50 mL of iohexol 300 mg iodine/mL (Omnipaque 300) to 950 mL of diluent.
-To achieve 1,000 mL at a final concentration of iohexol 15 mg iodine/mL, add 43 mL of iohexol 350 mg iodine/mL (Omnipaque 350) to 957 mL of diluent.
-To achieve 1,000 mL at a final concentration of iohexol 18 mg iodine/mL, add 75 mL of iohexol 240 mg iodine/mL (Omnipaque 240) to 925 mL of diluent.
-To achieve 1,000 mL at a final concentration of iohexol 18 mg iodine/mL, add 60 mL of iohexol 300 mg iodine/mL (Omnipaque 300) to 940 mL of diluent.
-To achieve 1,000 mL at a final concentration of iohexol 18 mg iodine/mL, add 52 mL of iohexol 350 mg iodine/mL (Omnipaque 350) to 948 mL of diluent.
-To achieve 1,000 mL at a final concentration of iohexol 21 mg iodine/mL, add 88 mL of iohexol 240 mg iodine/mL (Omnipaque 240) to 912 mL of diluent.
-To achieve 1,000 mL at a final concentration of iohexol 21 mg iodine/mL, add 70 mL of iohexol 300 mg iodine/mL (Omnipaque 300) to 930 mL of diluent.
-To achieve 1,000 mL at a final concentration of iohexol 21 mg iodine/mL, add 60 mL of iohexol 350 mg iodine/mL (Omnipaque 350) to 940 mL of diluent.
Injectable Administration
-Visually inspect parenteral products for particulate matter and discoloration prior to administration whenever solution and container permit. The solution should be clear and colorless to pale yellow. If discoloration or particulate matter is present, do not use.
-Iohexol injection may be administered at either body (37 degrees C) or room temperature.
Intravenous Administration
Bulk packaging
-For use only with an automated contrast injection system, contrast management system, or contrast media transfer set approved for use with iohexol.
-Bulk packaging is to be used only in a room designated for radiological procedures that involve intravascular administration of a contrast agent.
-Use aseptic technique when transferring iohexol from the bulk packaging. The container closure may be penetrated only 1 time with a suitable sterile component of the automated contrast injection system, contrast management system, or contrast media transfer set approved for use with iohexol.
-If 0.9% Sodium Chloride Injection is used, the IV administration port of the 0.9% Sodium Chloride Injection container may be penetrated only 1 time with a suitable sterile component of the contrast management system approved for use with iohexol.
-Once the iohexol container is punctured, maintain the bottle in an inverted position.
-Do not remove the bulk packaging from work area once the container enclosure is punctured. Discard if the integrity of the bulk packaging, 0.9% Sodium Chloride Injection, and delivery system cannot be assured through direct continuous supervision.
-Storage: A maximum use time of 8 hours from initial closure entry is permitted to complete fluid transfer. Discard any unused iohexol and 0.9% Sodium Chloride Injection 8 hours after initial puncture of the stopper.
Single-dose bottles
-Use aseptic technique for all handling and administration of iohexol for intravascular administration.
-Storage: A maximum use time of 4 hours from initial closure entry is permitted with a contrast media management system. Each bottle is intended for 1 procedure only. Discard any unused portion.
Intravenous injection
-Do not mix iohexol with, or inject in intravenous lines containing, other drugs or total nutritional admixtures.
-Avoid extravasation when administering iohexol injection intravascularly, especially in patients with severe arterial or venous disease.
-Hydrate patients before and after intravascular administration of iohexol injection.
Automated contrast injection system
-Iohexol may be used for computed tomography (CT) of the head and body with an automated contrast injection system cleared for use with contrast media. See device labeling for information on device indications, instructions for use, and techniques to help assure safe use.
Contrast media management system
-Iohexol bulk packaging and 300 and 350 mg iodine/mL in 150 mL single-dose bottles may be used for CT of the head and body with a contrast media management system cleared for such use. See device labeling for information on device indications, instructions for use, and techniques to help assure safe use.
-The container closure may be penetrated only 1 time with a suitable sterile component of the contrast media management system.
-Once the container is punctured, do not remove the bottle from the work area during the entire period of use.
Intrathecal Administration
-NOTE: Use care to avoid inadvertent intrathecal administration of iohexol 140 mg iodine/mL (Omnipaque 140) or 350 mg iodine/mL (Omnipaque 350). These concentrations are not intended for intrathecal use. Only iohexol 180 mg iodine/mL (Omnipaque 180), 240 mg iodine/mL (Omnipaque 240), or 300 mg iodine/mL (Omnipaque 300) concentrations may be administered via the intrathecal route.
-Inject slowly, over 1 to 2 minutes, to minimize excessive mixing of the solution with cerebrospinal fluid (CSF). In addition, slow injection will minimize premature cephalad (cranial) dispersion of iohexol. Depending on the volume of contrast medium estimated to be required, a small amount of CSF may be removed to minimize distention of the subarachnoid spaces. Once the contrast medium is injected, the needle can be removed.
-Neuroleptic drugs (including phenothiazines) should be held for at least 48 hours before and for at least 24 hours after the procedure.
Management of patients during procedure
-The patient should remain still during the procedure and not move unless instructed. Abrupt activity can cause excessive mixing of iohexol with CSF. If the patient must be moved, it is preferable for trained personnel to move the patient slowly.
-Avoid early and high cephalad dispersion, and an intracranial bolus. To maintain iohexol solution as a bolus, the medium can be moved distally very slowly under fluoroscopic control. The patient's head should remain elevated above the highest level of the spine. The head of the table should not be lowered more than 15 degrees during thoraco-cervical procedures. In patients with excessive curvature of the lumbar spine, consider a lateral position for the injection and movement of the medium cephalad.
Management of patients post-procedure
-Patients should remain in a bed with the head raised (30 to 45 degrees angle) for 12 to 24 hours post procedure. Advise patients to remain quiet and still for the first 24 hours with their head in the up position. Closely observe the patient during this time period
-Alternatively, recent evidence suggests that maintaining patients in an upright position post myelography (via a wheelchair or ambulation) may help minimize adverse effects.
Other Injectable Administration
Intra-Arterial Administration
-Mechanical or hand injection can be used to administer 1 or more bolus intra-arterial injections of iohexol.
-Use aseptic technique for all handling and administration of iohexol for intravascular administration.
-Do not mix iohexol with other drugs.
-Avoid extravasation when administering iohexol injection intravascularly, especially in patients with severe arterial or venous disease.
-Hydrate patients before and after intravascular administration of iohexol injection.
Intra-Articular Administration
-Arthrography is usually performed under local anesthesia.
-Fluoroscopic control should be used to ensure proper needle placement, prevent extracapsular injection, and prevent dilution of contrast medium.
-Do not exert undue pressure during injection.
Intra-Uterine Administration
-In an effort to reduce pain during the procedure, injection pressure and volume should be such that disruptive distention of the ducts examined is minimized.
Intravesical (Bladder) Instillation Administration
-Fill the bladder at a steady rate, exercising caution to avoid excessive pressure.
-May be diluted with Sterile Water for Injection.
-Dilutions should be prepared just prior to use; discard the unused portion after the procedure.
-For a final concentration of iohexol 100 mg iodine/mL, add 140 mL of Sterile Water for Injection to 100 mL of iohexol 240 mg iodine/mL (Omnipaque 240).
-For a final concentration of iohexol 100 mg iodine/mL, add 200 mL of Sterile Water for Injection to 100 mL of iohexol 300 mg iodine/mL (Omnipaque 300).
-For a final concentration of iohexol 100 mg iodine/mL, add 250 mL of Sterile Water for Injection to 100 mL of iohexol 350 mg iodine/mL (Omnipaque 350).
-For a final concentration of iohexol 90 mg iodine/mL, add 167 mL of Sterile Water for Injection to 100 mL of iohexol 240 mg iodine/mL (Omnipaque 240).
-For a final concentration of iohexol 90 mg iodine/mL, add 233 mL of Sterile Water for Injection to 100 mL of iohexol 300 mg iodine/mL (Omnipaque 300).
-For a final concentration of iohexol 90 mg iodine/mL, add 289 mL of Sterile Water for Injection to 100 mL of iohexol 350 mg iodine/mL (Omnipaque 350).
-For a final concentration of iohexol 80 mg iodine/mL, add 200 mL of Sterile Water for Injection to 100 mL of iohexol 240 mg iodine/mL (Omnipaque 240).
-For a final concentration of iohexol 80 mg iodine/mL, add 275 mL of Sterile Water for Injection to 100 mL of iohexol 300 mg iodine/mL (Omnipaque 300).
-For a final concentration of iohexol 80 mg iodine/mL, add 338 mL of Sterile Water for Injection to 100 mL of iohexol 350 mg iodine/mL (Omnipaque 350).
-For a final concentration of iohexol 70 mg iodine/mL, add 243 mL of Sterile Water for Injection to 100 mL of iohexol 240 mg iodine/mL (Omnipaque 240).
-For a final concentration of iohexol 70 mg iodine/mL, add 330 mL of Sterile Water for Injection to 100 mL of iohexol 300 mg iodine/mL (Omnipaque 300).
-For a final concentration of iohexol 70 mg iodine/mL, add 400 mL of Sterile Water for Injection to 100 mL of iohexol 350 mg iodine/mL (Omnipaque 350).
-For a final concentration of iohexol 60 mg iodine/mL, add 300 mL of Sterile Water for Injection to 100 mL of iohexol 240 mg iodine/mL (Omnipaque 240).
-For a final concentration of iohexol 60 mg iodine/mL, add 400 mL of Sterile Water for Injection to 100 mL of iohexol 300 mg iodine/mL (Omnipaque 300).
-For a final concentration of iohexol 60 mg iodine/mL, add 483 mL of Sterile Water for Injection to 100 mL of iohexol 350 mg iodine/mL (Omnipaque 350).
-For a final concentration of iohexol 50 mg iodine/mL, add 380 mL of Sterile Water for Injection to 100 mL of iohexol 240 mg iodine/mL (Omnipaque 240).
-For a final concentration of iohexol 50 mg iodine/mL, add 500 mL of Sterile Water for Injection to 100 mL of iohexol 300 mg iodine/mL (Omnipaque 300).
-For a final concentration of iohexol 50 mg iodine/mL, add 600 mL of Sterile Water for Injection to 100 mL of iohexol 350 mg iodine/mL (Omnipaque 350).
Because measurable plasma concentrations of iohexol are attained following intrathecal administration and possibly after injection into body cavities or oral administration, adverse reactions associated with intravascular administration of iohexol are theoretically possible when used by any route of administration.
Adverse reactions to contrast media like iohexol can generally be classified as idiosyncratic (unpredictable, not related to dosage) or chemotoxic (related to dosage, osmolality, viscosity, hydrophilicity, etc.). Idiosyncratic reactions occur more frequently in patients 20 to 40 years old. Most patients tolerate contrast media injections without sequelae and 95% of reactions to nonionic contrast media are mild to moderate; however, life-threatening reactions, usually cardiovascular in nature, can occur. The incidence of adverse reactions has been dramatically reduced by the introduction of low osmolar contrast media. In a study of over 300,000 patients comparing intravenous administration of ionic vs. nonionic contrast media, adverse reactions were reduced from 12.66% with ionic contrast media to 3.13% (p < 0.01) with nonionic contrast media. More importantly, the incidence of severe reactions (including shortness of breath, sudden drop in blood pressure, loss of consciousness, and cardiopulmonary arrest) were reduced from 0.22% with ionic contrast media to 0.04% with nonionic contrast media (p < 0.01).
In vitro studies with animal blood showed that many radiopaque contrast agents (e.g., iohexol) may produce transient changes in red cell and leukocyte counts, serum calcium, serum creatinine, serum aspartate aminotransferase (AST), and uric acid in urine; transient albuminuria may occur. These findings have not been associated with clinical manifestations.
Nonionic contrast media are associated with fewer adverse reactions than ionic in children; the majority of adverse reactions in children are minor in nature. In controlled clinical trials of intravascular iohexol involving 391 pediatric patients, the incidence of adverse reactions was generally less than in adults. In a study comparing ionic and nonionic contrast media for CT studies in children, minor side effects were detected in 85% of children receiving meglumine diatrizoate, 18% of children receiving iohexol, and 36% of children receiving iopamidol. All adverse reactions occurred with a much lower frequency in the iopamidol and iohexol groups. Among the most common adverse reactions in this study were abnormal taste, additional movements, itching and local discomfort. In controlled clinical trials involving 152 patients for pediatric myelography by lumbar puncture, adverse events following the use of iohexol 180 mg iodine/mL (Omnipaque 180) were generally less frequent than with adults. Reactions reported with an incidence of less than 0.7% include pyrexia, hives, stomachache, visual hallucination, and neurological changes. All were transient and mild with no clinical sequelae.
Severe reactions, including cardiovascular collapse, cardiac arrest, unconsciousness, shock, and death, have been reported with iohexol use. These life-threatening reactions tend to be unpredictable. The estimated incidence of shock after the administration of iodinated contrast media is 1 per 20,000 patients (0.005%), and the reported incidence of death ranges from 6.6 per 1 million patients (0.00066%) to 1 in 10,000 patients (0.01%). Most deaths occur during injection or the first 5 to 10 minutes. Nausea and vomiting may be the first sign of a severe reaction. If nausea or vomiting occurs during injection, the injection rate should be slowed or stopped. In a study comparing ionic and nonionic contrast media for CT studies in children, nausea and vomiting were among the most common adverse reactions. In controlled clinical trials involving 152 patients for pediatric myelography by lumbar puncture, adverse events after the use of iohexol 180 mg iodine/mL (Omnipaque 180) were generally less frequent than with adults. The incidence of vomiting was 6%. Vomiting (9%) and nausea (5%) were also among the most commonly reported adverse events during oral administration in pediatric patients.
Hypersensitivity reactions, including anaphylactoid reactions, can occur in up to 15% of patients receiving contrast media such as iohexol. The incidence of severe anaphylactoid reactions is 0.04% to 0.22%. Those patients at higher risk for hypersensitivity-type reactions are those with asthma, a history of allergies to drugs or foods, and those with a history of previous radiopaque contrast media hypersensitivity. Most reactions occur within 1 to 3 minutes, but delayed hypersensitivity reactions can occur as long as 3 days to 1 week after administration of contrast media. Symptoms of hypersensitivity range from mild, including nasal congestion, sneezing, itching, pruritus, and rash, to severe, including urticaria, swelling, laryngeal edema, bronchospasm, wheezing, and anaphylactic shock. The incidence of delayed hypersensitivity is less than 4%, with the most common presentation being maculopapular rash; other symptoms such as urticaria and angioedema may also be present. Urticaria (2%) was also among the most commonly reported adverse events during oral administration of iohexol in pediatric patients.
The administration of contrast media such as iohexol is associated with nephrotoxicity. The definition of contrast-induced nephrotoxicity (CIN) varies but is generally recognized as a rise in serum creatinine of at least 25% to 50% or more than 0.5 mg/dL over baseline. Symptoms of nephrotoxicity can range from elevations in serum creatinine to oliguria, anuria, and acute renal failure (unspecified) requiring dialysis. The incidence of nephrotoxicity is difficult to estimate as clinical trials have varied with respect to definition of nephrotoxicity, procedure, volume of contrast media, and patient risk factors. Studies have suggested an incidence of up to 10% in patients with normal renal function; in patients with various risk factors, the incidence rises to anywhere from 12% to 50%. Treatment of acute renal failure from contrast media is supportive; dialysis is indicated only if clinically needed. If a patient requires another procedure or exam requiring contrast media, renal function should return to baseline, and the patient should be well hydrated before re-examination. Occasionally, transient proteinuria and, rarely, oliguria and anuria have been reported with intravascular iodinated contrast media administration.
Iodine-containing contrast medium can adversely affect thyroid function, resulting in either hypothyroidism or hyperthyroidism. Hypothyroidism or transient thyroid suppression has been reported in 1% to 15% of young pediatric patients (age birth to 3 years), with the incidence depending on the age of the patient and the dose of the iodinated contrast agent. Monitor young pediatric patients closely for thyroid dysfunction. If thyroid dysfunction is detected, treat and monitor thyroid function as clinically needed. Thyroid storm has occurred after the intravascular use of iodinated contrast agents in patients with hyperthyroidism, or with an autonomously functioning thyroid nodule.
Iohexol 140 mg iodine/mL (Omnipaque 140) and 350 mg iodine/mL (Omnipaque 350) concentrations are not indicated for intrathecal administration. Use care to assure these solutions are not administered intrathecally. Severe and fatal neurotoxic adverse reactions, including convulsions, cerebral hemorrhage, unconsciousness, paralysis, arachnoiditis, hyperthermia, and brain edema, have been reported when inadvertent intrathecal administration of ionic and nonionic contrast media occurs. Also, renal failure, cardiac arrest, and rhabdomyolysis have been reported.
Regardless of the contrast agent employed, the overall estimated incidence of serious adverse reactions is higher with coronary arteriography than with other procedures. Hemodynamically, when contrast agents are injected intravascularly, arteriolar vasodilation and increases in left ventricular end-diastolic pressure develop secondary to intravascular volume expansion and depressed myocardial function. Also, patients may become bradycardic and hypotensive. Electrophysiologic changes associated with the intracoronary injection of contrast media include depressed atrioventricular node conduction and sinoatrial node automaticity. In addition, patients are more susceptible to ventricular fibrillation or tachycardia. Cardiac arrest, serious arrhythmias, sinus bradycardia (1%), ECG changes, hypotension (2.5%), angina pectoris (8%), myocardial ischemia, or myocardial infarction have been reported when iohexol is used intravascularly, but these reactions occur more frequently during cardioarteriography and ventriculography. Hypotension (2%) was among the most commonly reported adverse events during oral administration of iohexol in pediatric patients. In general, nonionic contrast media are associated with a lower incidence of severe cardiac reactions, although some controversy exists. Not only do nonionic contrast media have fewer cardiac reactions, but the buffer or stabilizer used in iohexol, edetate calcium disodium, does not bind calcium as avidly as stabilizers used in some ionic contrast media. The use of edetate calcium disodium is an additional factor leading to less cardiovascular toxicity with iohexol.
There are some adverse reactions that occur more commonly during cerebral arteriography using iohexol, such as convulsions, somnolence, paresis, and visual impairment (i.e., photoma 15%). Also, cardiovascular reactions, specifically bradycardia and blood pressure fluctuations might also be more common during cerebral arteriography than during other procedures.
Intravascular injection of iohexol is associated with the sensation of warmth, pain, and flushing/hot flashes, especially in peripheral arteriography and venography. This side effect is thought to be due to peripheral vasodilation and is related to the osmolality of the contrast media; the frequency of such sensations has been reduced with the use of nonionic contrast media. Also, the incidence of leg pain with phlebography has been reported to be 21%. The pain was usually mild and lasted a short time after injection. In a study comparing ionic and nonionic contrast media for CT studies in children, warmth and flushing were among the most common adverse reactions.
Injection site reaction to iohexol, including swelling and erythema, is most often due to extravasation of the contrast medium. The symptoms generally diminish rapidly. However, skin necrosis, tissue necrosis, and ulceration have been reported with large volumes of extravasated contrast medium. If extravasation occurs, the affected limb should be elevated. Also, heat or cold applied to the affected area have been reported to be successful in treating extravasation.
Some adverse reactions that occur may be a consequence of the procedure, such as bleeding, pseudoaneurysm at the puncture site, or brachial plexus palsy after axillary artery injections. During aortography, the risks of the procedure itself include injury to the aorta and neighboring organs, pleural puncture, renal damage including infarction and renal tubular necrosis, accidental selective filling of the right renal artery during the translumbar procedure in the presence of preexisting renal disease, retroperitoneal bleeding from the translumbar approach, and spinal cord injury and pathology associated with the syndrome of transverse myelitis. Thromboembolism, venous thrombosis, displacement of arterial plaques, stroke, dissection of the coronary vessels, and transient sinus arrest are rare complications. While clinical manifestations have not been noted, in vitro studies with animal blood show that many radiopaque contrast agents such as iohexol produce a slight decrease of plasma coagulation factors including prothrombin time, partial thromboplastin time, and fibrinogen, as well as a slight tendency to cause platelet and red blood cell aggregation.
In a study comparing ionic and nonionic contrast media for CT studies in children, dizziness was among the most common adverse reactions. In controlled clinical trials involving 152 patients for pediatric myelography by lumbar puncture, the incidence of headaches was 9% and backache was 1.3% after the use of iohexol 180 mg iodine/mL (Omnipaque 180). It should be noted that the incidence of headache in children after lumbar puncture alone has been reported to be as high as 20%. The most commonly reported adverse reactions associated with intrathecal iohexol include headache (18%), nausea (6%), vomiting (3%), mild to moderate pain (8%) including back pain, neck pain and stiffness, and neuropathic pain, and dizziness (2%). The reactions usually occur from 1 to 10 hours after injection. Most are usually mild to moderate and disappear within 24 hours. Headaches may be severe or persist for several days and are often accompanied by nausea and vomiting. Headaches tend to be more frequent and persistent in patients that are not adequately hydrated. If a patient experiences nausea and vomiting, initiate intravenous fluids to prevent dehydration. Also, because of the increased risk of seizure activity associated with intrathecal iohexol, do not use drugs from the phenothiazine class (i.e., prochlorperazine) to treat nausea and vomiting.
Major motor seizures have been reported with iohexol use. Transitory EEG changes occur and usually take the form of slow-wave activity. If intracranial entry of the medium occurs, consider prophylactic anticonvulsant treatment with barbiturates. Early onset of seizures (less than 2 hours) is indicative of early substantial intracranial entry. Intravenous diazepam or phenobarbital sodium are recommended if seizures occur. In most reported cases of seizures with nonionic contrast media used during myelography, 1 or more of the following is usually present: deviations from recommended procedure in myelographic management; use in patients with a history of epilepsy; overdosage; intracranial entry of a bolus or premature diffusion of a high concentration of the medium; medication with neuroleptic drugs or phenothiazine antinauseants; failure to maintain elevation of the head during the procedure, on the stretcher, or in bed; or excessive and particularly active patient movement or straining.
Neurological adverse events that have been associated with intrathecal contrast media, including iohexol, are a feeling of heaviness, ataxia, weakness (including muscle weakness), emotional distress, syncope, vertigo, irritability, hostility, hallucinations, psychosis, tinnitus, fever, fatigue, drowsiness, insomnia, transient perceptual aberrations (depersonalization, anxiety, depression, hyperesthesia, speech, hearing, or visual disturbances, disorientation), photophobia, diplopia, amblyopia, hyperreflexia or areflexia, hypertonia or flaccidity, restlessness, asterixis, and dysphasia. Rare, severe mental disturbances (various forms of aphasia and disorientation) usually appear 8 to 10 hours post-injection and last for up to 24 hours. However, apprehension, agitation, or progressive withdrawal to stupor or coma has been reported. In some cases, transient auditory and visual disturbances (believed subjective or delusional) have accompanied these severe mental disturbances. Persistent cortical loss of vision in association with convulsions and ventricular block has been reported. Rarely, persistent though transitory weakness in the leg or ocular muscles has been reported. Peripheral neuropathy has been rare and transitory; specific neuropathies include sensory and/or motor or nerve root disturbances, myelitis, persistent leg muscle pain or weakness, sixth nerve palsy, or cauda equina syndrome. Muscle cramps, fasciculation or myoclonia, spinal convulsion, paralysis, or spasticity are unusual and have responded promptly to a small dose of intravenous diazepam. In addition to the above mentioned adverse reactions, bacterial meningitis, aseptic meningitis syndrome (characterized by meningismus, headaches, nausea, vomiting, fever, confusion, and usually clears after 10 hours to 2 to 3 days post-procedure) and Guillain-Barre syndrome have been reported.
Orally administered hypertonic contrast media such as iohexol draw fluid into the intestines, which, if severe enough, could result in hypovolemia. Diarrhea is more common when high concentrations and volumes are administered. Likewise, in infants and young children, the occurrence of diarrhea may result in hypovolemia. Diarrhea (36%) is among the most commonly reported adverse events during oral administration of iohexol in pediatric patients. A shock-like state can occur, especially in the elderly, cachectic patients, small children, and infants. The incidence of mild and transient diarrhea has been reported to be as high as 42% in adults. Other reported adverse events with oral use include nausea (15%), vomiting (11%), abdominal pain (7%), flatulence (2%), and headache (2%). Fever (5%) and abdominal pain (2%) are among the most commonly reported adverse events during oral administration of iohexol in pediatric patients. Because both the oral and intravenous administrations of iohexol are used during CT examinations of the abdomen, patients should be evaluated for adverse events associated with intravascular routes of administration.
Transient pain (29%) and swelling (42%) are associated with injection of iohexol into the joint. Delayed, severe, and persistent discomfort can occur. The incidence of joint swelling and discomfort has decreased with the use of nonionic contrast media. Also, much of the discomfort associated with this route of administration is related to the procedure itself. Other reported adverse events include heat sensation (13%) and muscle weakness (0.7%). Hematoma at the injection site has been reported (0.7%). Injection of iohexol during endoscopic retrograde pancreatography (ERP)/endoscopic retrograde cholangiopancreatography (ERCP) is associated with transient pain (17%), although severe and persistent pain can occur for as long as 24 hours post-procedure. Other reported adverse events include hypertension (1%), somnolence (1%), and burning (1%). Vomiting and diarrhea have also been reported. Injection of iohexol during hysterosalpingography is associated with immediate but transient pain (49%). Monitor injection pressure and volume instilled to minimize pain and avoid disruptive distention of the uterus and fallopian tubes; fluoroscopic monitoring is recommended. Somnolence (3%), fever (3%), and nausea (3%) have also been reported. Pain (7%) has been associated with iohexol use during herniography. In addition, headache (3%), diarrhea (3%), flatulence (10%), and unwell feeling (3%) have been reported.
It is expected that adverse reactions reported with 1 iodinated contrast medium are possible with any other water-soluble iodinated contrast media. Cardiovascular type reactions such as vasodilation (feeling of warmth), flushing, cerebral hematomas, hemodynamic disturbances, chest pain (unspecified), sinus bradycardia, transient electrocardiographic abnormalities, arrhythmias, conduction defects, asystole, cardiopulmonary arrest, arterial spasms, sinus tachycardia, hypertension, hypertensive crisis, transient ischemic attack, thrombophlebitis, petechiae, peripheral edema, false aneurysm, disseminated intravascular coagulation (DIC), and vasovagal reactions have been reported. Digestive system reactions including nausea, vomiting, severe unilateral or bilateral swelling of the parotid and submaxillary glands, dry mouth (xerostomia), anorexia, retching, choking, abdominal cramps, dyspepsia, and diarrhea have been reported. Also, nervous system reactions including headache, stiff neck, confusion, dizziness, drowsiness, paresthesias, involuntary movements, tremor, convulsions, paralysis, coma, temporary cortical blindness, nystagmus, and temporary amnesia have been reported. Respiratory-related adverse effects have been reported and include increased cough, sneezing, asthma, wheezing, hypoxia, apnea, dyspnea, laryngeal edema, pulmonary edema, bronchospasm or laryngospasm, nasal congestion, rhinitis, throat constriction, and cyanosis. Other reported adverse effects include periorbital edema, facial edema, malaise, pallor, fever, chills, profuse diaphoresis and/or increased sweating (hyperhidrosis), rash, urticaria, purpura, ecchymosis, abscess, lacrimation, osmotic nephrosis of proximal tubular cells, polyuria, renal failure, urinary retention, hematuria, dysgeusia (perversion of taste), visual disturbances, bilateral ocular irritation, itching, conjunctival chemosis, infection, and conjunctivitis. Neutropenia has been reported with other contrast media and is possible with iohexol.
Iodinated contrast agents have been associated with severe cutaneous adverse reactions, including Stevens-Johnson Syndrome (SJS), toxic epidermal necrolysis (TEN), acute generalized exanthematous pustulosis (AGEP), and drug reaction with eosinophilia and systemic symptoms (DRESS). The reaction onset ranges from 1 hour to several weeks after intravascular drug administration; however, repeat drug exposure may shorten the time to onset and increase the reaction severity. Prophylactic medications may not prevent or mitigate these reactions.
Peripheral angiography with iohexol should be performed with caution, if at all, in patients with severe ischemia; pulsation should be present in the artery to be injected.
Because of overdosage considerations and the increased risk of neurotoxicity, immediate repeat myelography in the event of technical failure is contraindicated. At least 48 hours should lapse between procedures with 5 to 7 days preferred. Direct intracisternal or ventricular administration of iohexol for standard radiography (without computerized tomographic enhancement) is not recommended. Inadvertent intracranial entry of a large or concentrated bolus of the contrast medium, which increases the risk of neurotoxicity, can be prevented by careful patient management. Also, effort should be directed to avoid rapid dispersion of the medium causing inadvertent rise to intracranial levels (e.g., by active patient movement). If such intracranial entry of the medium occurs, prophylactic anticonvulsant treatment with barbiturates should be considered. Patients receiving anticonvulsants should be maintained on these medications. Furthermore, in patients with a history of seizure disorders not on anticonvulsant therapy, prophylactic barbiturates should be considered. In order to minimize the risk of overdosage and neurotoxicity, recommended neuroradiographic procedures and patient management strategies including adherence to dosage guidelines should be followed.
Serious, life-threatening, or fatal anaphylactoid or cardiovascular reactions have been reported with the use of contrast media like iohexol. The majority of fatal reactions occur during injection or the first 5 to 10 minutes after injection with cardiac arrest being the most prevalent feature; cardiovascular disease is the main aggravating factor. Patients at increased risk of anaphylactoid reactions are those with a history of radiopaque contrast media hypersensitivity, iodine hypersensitivity, asthma, and atopy (including hay fever, food allergies, and drug allergies). Both acute and delayed hypersensitivity reactions have been reported after contrast media exposure. Acute hypersensitivity reactions to contrast media are thought to be mediated by the release of vasoactive substances such as histamine, serotonin and bradykinin; in contrast, delayed-hypersensitivity reactions that can occur as long as 3 to 7 days after contrast media exposure are most likely caused by antigen-antibody reactions. In addition, it appears that the incidence of hypersensitivity reactions is higher with intravenous administration of contrast media. The incidence of hypersensitivity reactions has been reduced with the use of nonionic contrast media. In patients at risk of hypersensitivity (including those patients with previous allergic reaction to contrast media), premedication with corticosteroids and antihistamines has been shown to reduce the incidence and severity of hypersensitivity reactions. Reportedly, 16% to 44% of patients with previous history of hypersensitivity reactions to contrast media will have an allergic reaction upon second exposure; utilizing nonionic contrast media and premedicating at-risk patients reduces the incidence of hypersensitivity during repeat exposure to 10%. Pretesting patients for the likelihood of an allergic type reaction is not recommended as it is not reliable and it may be dangerous to the patient. Diagnostic procedures that involve the use of any radiopaque agent should be carried out under the direction of personnel with prerequisite training and a thorough knowledge of the particular procedure to be performed. Appropriate facilities should be available for coping with any complication of the procedure, as well as for emergency treatment of severe reaction to the contrast agent itself. After parenteral administration of a radiopaque agent, competent personnel and emergency facilities should be available for at least 30 to 60 minutes since severe delayed reactions may occur.
Serious, rarely fatal, thromboembolic events causing myocardial infarction and stroke have been reported during angiographic procedures with ionic and nonionic contrast media. Controversy exists as to whether nonionic contrast media such as iohexol are more thrombogenic than ionic contrast media. The American College of Cardiology recommended to consider the concomitant administration of heparin to patients when nonionic agents were used; however, this recommendation has been refuted by some authors as they believe the angioplasty procedure itself is thrombogenic, not the contrast media. Because many factors contribute to thromboembolic events including length of procedure, catheter and syringe material, underlying disease state, and concomitant medications, meticulous intravascular technique is necessary to minimize thromboembolic events. Measures that should be considered to minimize this risk include close attention to guidewire and catheter manipulation, use of manifold systems or 3-way stopcocks, frequent catheter flushing with heparinized saline solutions, and minimizing the length of the procedure. Clotting has been reported when blood remains in contact with syringes containing nonionic contrast media; the use of plastic syringes in place of glass may minimize in vitro clotting. In addition, the possibility of dislodging plaques or damaging or perforating the vessel wall can occur during catheter manipulations and contrast medium injection. Test injections to ensure proper catheter placement may be prudent. Special care is necessary when venography is performed in patients with suspected thromboembolic disease such as thrombosis, phlebitis, severe ischemic disease, or a totally obstructed venous system. Because of the increased risk of inducing thrombosis or embolism associated with the procedure, angiography should be avoided whenever possible in patients at increased risk of thromboembolism (including those with a coagulopathy or homocystinuria).
Both ionic and nonionic contrast media can cause nephrotoxicity including acute renal failure sometimes requiring dialysis. The definition of contrast-induced nephrotoxicity (CIN) varies but is generally recognized as a rise in serum creatinine of at least 25% to 50% or more than 0.5 mg/dL over baseline. Risk factors for CIN include advanced age, pre-existing renal impairment (usually defined as a creatinine clearance less than 50 to 60 mL/minute), combined renal disease and hepatic disease, diabetes mellitus, dehydration, ejection fraction 40% or lower, females, excretory urography, repeat contrast media exposure within 72 hours, reduced effective arterial volume (i.e., cirrhosis and nephrosis), contrast media type (e.g., ionic contrast media is associated with a higher incidence of CIN than nonionic), and contrast media dose (e.g., higher doses of contrast media are associated with more nephrotoxicity). The patient's risk factors should be taken into consideration before administering contrast during an exam or procedure as the presence of multiple risk factors increases the risk for CIN considerably. The most compelling risk factors for CIN are pre-existing renal impairment, and pre-existing renal impairment plus diabetes mellitus. Diabetic patients with a serum creatinine more than 3 mg/dL should not be examined with iohexol unless the possible benefits of the examination clearly outweigh the additional risk. Furthermore, excretory urography should proceed with caution immediately after surgery in renal transplant patients. It may be prudent for all patients with a history of renal insufficiency, diabetes mellitus, or advanced age to have a baseline serum creatinine checked and creatinine clearance calculated prior to the procedure or exam. Do not use iohexol in patients with anuria. Preventive measures should be considered in all patients regardless of risk factors. Adequate hydration has repeatedly been the only intervention to show success in reducing the incidence of CIN. In addition to hydration, the use of nonionic contrast media and avoiding the concomitant use of nephrotoxic drugs (i.e., non-steroidal anti-inflammatory drugs, aminoglycosides, etc.) may be prudent. Several studies have evaluated the use of n-acetylcysteine (600 mg PO twice daily for 2 days given the day prior to and the day of the procedure or exam); while conflicting data exists, it appears that n-acetylcysteine may provide some benefit in preventing CIN in high-risk patients. Furthermore, some data indicate that the effects of n-acetylcysteine may be dose-dependent. In patients with myocardial infarction undergoing angioplasty, n-acetylcysteine 1,200 mg IV prior to angioplasty followed by 1,200 mg PO twice daily for 48 hours has been reported to be significantly more effective at reducing the incidence of CIN vs. a lower dose or placebo. Other interventions including administration of loop diuretics, calcium antagonists, mannitol, theophylline, or low-dose dopamine have not been successful.
Iohexol should be used cautiously in patients with multiple myeloma; anuria has been reported in this group of patients after receiving contrast media. Although originally thought to be a contraindication to receiving contrast media, it is recognized that the occurrence of anuria or renal impairment in patients with multiple myeloma is probably due to a pre-existing state of dehydration rather than an interaction between the disease itself and the contrast media. If the need arises, patients with multiple myeloma can receive contrast media, but they should be well hydrated prior to the procedure or exam. In addition, partial dehydration may predispose this population of patients to precipitation of the myeloma protein in the renal tubules further increasing the risk of nephrotoxicity. No form of therapy has been effective in reversing this effect.
Contrast media may promote sickling in individuals who are homozygous for sickle cell disease. Patients with sickle cell disease tend to be dehydrated during an acute sickle cell crisis. If iohexol is used in this population, patients should be adequately hydrated.
Contrast media should be used cautiously in patients with congestive heart failure. Patients with heart failure are at risk of fluid overload and may not be able to tolerate the recommended hydration regimen used in the prevention of contrast-induced nephropathy (CIN). In addition, while iohexol is considerably less hyper-osmolar when compared to the ionic agents such as diatrizoate, iohexol can cause a transient increase in circulatory volume. In a study evaluating the effects of n-acetylcysteine on the prevention of CIN, patients with left ventricular ejection fractions <= 40% developed CIN at a rate of almost 3 times that of patients with an ejection fraction of > 40%. The combination of low ejection fraction and a creatinine clearance <= 60 mL/min was associated with a 5 times increased incidence of CIN. Following contrast media administration, patients with congestive heart failure should be observed closely for several hours.
The administration of ionic contrast media has been associated with an unpredictable release of catecholamines and severe hypertensive crisis in patients with pheochromocytoma. If the use of contrast media is determined to be necessary, nonionic contrast media such as iohexol should be used preferentially and the volume of contrast media used should be minimized. In addition, blood pressure should be measured throughout the procedure with equipment necessary to treat a hypertensive crisis available. In the past, the use of alpha-blockers and potentially even beta-blockers prior to the administration of contrast media in patients with known pheochromocytoma has been recommended by some authors; however recent evidence indicates that such preventive measures may not be necessary when using nonionic contrast media as the risk for hypertensive crisis is lessened.
The exacerbation of myasthenia gravis has been reported after the use of iohexol. It has been suggested that contrast media such as iohexol can increase neuromuscular blockage and that those patients with bulbar signs and requiring high doses of contrast media are at higher risk for this complication.
Administration of iohexol may result in adverse effects on the thyroid. Reports of thyroid storm have been associated with the use of iodinated radiopaque diagnostic agents in patients with preexisting thyroid disease such as hyperthyroidism, thyrotoxicosis, or an autonomously functioning thyroid nodule. Because the frequency of autonomous thyroid nodules increases with age, older patients may be at increased risk for developing a thyroid storm. Conversely, transient thyroid suppression has been infrequently reported in both adult and pediatric populations. In some cases, drug recipients required treatment for hypothyroidism. Prior to administering iohexol, evaluate all patients for thyroid-associated risk factors.
Cerebral arteriography with iohexol should be undertaken with extreme care in patients in poor clinical condition, of an advanced age, with advanced arteriosclerosis, with severe arterial hypertension, with recent cerebral embolism or thrombosis, and with cardiac decompensation.
Selective coronary arteriography should be performed only in selected patients where the expected benefits outweigh the procedural risk. Manufacturers of similar iodinated contrast media recommend ECG monitoring during this procedure. Contrast media injected directly into coronary arteries or chambers of the heart may cause ECG changes such as a transient prolongation of the RR and QT intervals. Selective coronary arteriography should be used with caution in patients with congenital or acquired QT prolongation syndromes as QT prolongation can predispose patients to serious arrhythmias including torsades de pointes. In addition, contrast media injected directly into coronary arteries or chambers of the heart causes myocardial contraction depression and is associated with bradycardia and hypotension lasting 5 to 10 seconds. Most patients recover from this effect without treatment; however, in select patients including those with severe cardiac disease (i.e., coronary artery obstruction, heart failure, ischemic heart disease, valvular heart disease, pulmonary hypertension, etc.), these hemodynamic effects can cause ischemia and profound hypotension possibly leading to myocardial infarction or death. The risk of cardiovascular reactions is less with nonionic contrast media (i.e., iohexol) than ionic. In terms of overall cardiovascular safety, nonionic contrast media such as iohexol tend to be less arrhythmogenic and cause less hemodynamic and electrophysiologic changes than their ionic counterparts.
Angiocardiography should proceed with caution in patients with chronic pulmonary emphysema, according to the manufacturer. Reported effects of iodinated contrast media such as iohexol on lung function include bronchospasm, pulmonary edema, increased pulmonary vascular resistance, and histamine release from lung mast cells and basophils and these effects can contribute to adverse effects in patients with pulmonary disease including emphysema and asthma.
Avoid extravasation of iohexol, especially in those patients with arterial insufficiency, compromised venous drainage, or compromised lymphatic systems. Fluoroscopy is recommended. Extravasation of nonionic contrast media is better tolerated than ionic contrast media; however, severe reactions have been reported with both types of media. If extravasation occurs, elevate the affected limb. Also, heat or cold applied to the affected area has been reported to be successful in treating extravasation.
Evaluate thyroid function based on underlying risk factors in neonates, infants, and children 3 years or younger after exposure to an iodinated contrast media, especially in term and premature neonates. Hypothyroidism or transient thyroid suppression has been reported in pediatric patients (age birth to 3 years) after both single and multiple exposures to iodinated contrast media, such as iohexol. Younger age, very low birth weight, prematurity, underlying medical conditions affecting thyroid function, admission to neonatal or pediatric intensive care units, and congenital cardiac conditions are associated with increased risk for hypothyroidism or thyroid suppression. Pediatric patients with congenital cardiac conditions may be at the greatest risk as they often require high doses of contrast during invasive cardiac procedures, such as catheterization and computed tomography (CT). An underactive thyroid during early life may be harmful for cognitive and neurological development and may require thyroid hormone replacement therapy. Pediatric patients at higher risk of experiencing an adverse reaction during and after administration of any contrast agent may include those with asthma, hypersensitivity to other medication and/or allergens, cyanotic and acyanotic heart disease, congestive heart failure, a serum creatinine more than 1.5 mg/dL, immature renal function, dehydration, or those younger than 12 months.
Iohexol for hysterosalpingography is contraindicated during pregnancy or suspected pregnancy, within 6 months after termination of pregnancy, or within 30 days after conization or curettage. Hysterosalpingography is contraindicated in pregnant women due to the potential risk to the fetus from an intrauterine procedure. Data with iohexol use in pregnant women are insufficient to determine if there is a drug-associated risk of adverse developmental outcomes. Iohexol does cross the placenta and reach fetal tissues in small amounts. In animal reproduction studies, no adverse developmental effects were noted after IV administration to pregnant rats and rabbits during organogenesis at doses up to 0.4 and 0.5 times, respectively, the maximum recommended human IV dose. The American College of Radiology (ACR) manual on contrast media states that iodinated contrast crosses the human placenta and enters the fetus in measurable quantities; however, the risk to the fetus is unknown. Therefore, the ACR recommends iodinated contrast be administered during pregnancy only if necessary and only after informed consent is obtained. In contrast, the Guidelines for Computed Tomography and Magnetic Resonance Imaging in Pregnancy and Lactation state that use of iodinated contrast during pregnancy appears to be safe and should be administered as per usual. It is advised to screen neonates whose mothers received iodinated contrast during pregnancy for hypothyroidism.
Data are limited regarding use of iohexol during breast-feeding; however, exposure of the breast-fed infant to iodine is expected to be minimal. Iodinated contrast agents are excreted unchanged in human milk in very low amounts with poor absorption from the gastrointestinal tract of a breast-fed infant. Limited data demonstrate that breast-feeding after iohexol administration would result in the infant receiving an oral dose of 0.5% to 0.7% of the maternal weight-adjusted dose. To minimize potential exposure to the breast-fed infant, a lactating woman may consider interrupting breast-feeding and pumping and discarding breast milk for 10 hours (approximately 5 half-lives) after iohexol administration. The Guidelines for Computed Tomography and Magnetic Resonance Imaging Use During Pregnancy and Lactation and the American College of Radiology (ACR) manual on contrast media state that lactating women receiving iodinated contrast can continue to breast-feed without interruption. Previous American Academy of Pediatrics recommendations considered iohexol as compatible with breast-feeding. Consider the developmental and health benefits of breast-feeding along with the mother's clinical need for iohexol and any potential adverse effects on the breast-fed infant from iohexol or the underlying maternal condition.
Iodinated contrast media such as iohexol should be administered to geriatric patients with caution. Elderly patients are at increased risk of nephrotoxicity (due to age-related decline in renal function) and exacerbation of thyroid storm (due to age-related increases in autonomous thyroid nodules). In addition, elderly patients are at increased risk of adverse events during cerebral arteriography and myelography. Iohexol should be administered with caution and only if clinically indicated.
Iohexol 140 mg iodine/mL and 350 mg iodine/mL concentrations are contraindicated for intrathecal administration; however, iohexol 180 mg iodine/mL, 240 mg iodine/mL, and 300 mg iodine/mL concentrations can be administered by this route. Severe and fatal neurotoxic adverse reactions including convulsions, cerebral hemorrhage, unconsciousness, paralysis, inflammation of the arachnoid membrane, hyperthermia, and brain edema have been reported when inadvertent intrathecal administration of nonionic contrast media occurs. In addition, renal failure, cardiac arrest, and rhabdomyolysis have been reported.
Iohexol for hysterosalpingography is contraindicated during menstruation or when menstruation is imminent as well as when signs of an infection are present in any portion of the genital tract (including the external genitalia) or when reproductive tract neoplastic disease (e.g., cervical cancer, uterine cancer) is known or suspected because of the risk of peritoneal spread of neoplasm.
Because voiding cystourethrography (VCU) procedures require instrumentation, special precautions should be observed in patients known to have an acute urinary tract infection (UTI).
Concomitant use of intrathecal corticosteroid therapy with intrathecal iohexol is contraindicated. Myelography should not be performed in the presence of significant local or systemic infection where bacteremia or sepsis is likely. Inducing bacterial meningitis during intrathecal procedures should be considered; a sterile field should be maintained during spinal puncture.
The need for myelographic examination should be carefully evaluated. Iohexol should be administered only if medically necessary and with caution in patients that have increased intracranial pressure or suspicion of intracranial mass or tumor, abscess or hematoma, those with a history of seizures or convulsive disorder, severe cardiac disease, chronic alcoholism, multiple sclerosis, or elderly patients. Particular attention should be given to the state of hydration, concentration of medium, dose, and technique used in these patients. In addition, if frankly, bloody cerebrospinal fluid is observed, the possible benefits of a myelographic examination should be reconsidered.
Avoid use of iohexol in patients with a history of contrast-induced serious rash. Iodinated contrast agents have been associated with severe cutaneous adverse reactions, including Stevens-Johnson Syndrome (SJS), toxic epidermal necrolysis (TEN), acute generalized exanthematous pustulosis (AGEP), and drug reaction with eosinophilia and systemic symptoms (DRESS). The reaction onset ranges from 1 hour to several weeks after intravascular drug administration; however, repeat drug exposure may shorten the time to onset and increase the reaction severity. Prophylactic medications may not prevent or mitigate these reactions.
Parenteral administration of iohexol oral solution is contraindicated. Adverse reactions such as hemolysis may occur if the oral solution is administered intravascularly.
Iodinated contrast agents cause laboratory test interference with certain thyroid function tests. Results of protein-bound iodine (PBI) and radioactive iodine uptake studies, which depend on iodine estimations, will not accurately reflect thyroid function for up to 16 days after administration of iodinated contrast media such as iohexol. However, thyroid function tests that do not depend on iodine estimations (e.g., T3 resin uptake and total or free thyroxine (T4) assays) are not affected.
Patients should be well-hydrated prior to and following iohexol injection administration. A suggested common regimen in eligible patients (e.g., those patients in which fluid administration would not be contraindicated) is 1ml/kg/hr of 0.9% saline starting at least 4 hours prior to the procedure or exam and continuing for at least 12 hours after.
NOTE: In patients with a history of allergic reaction to contrast media, those with a history of asthma or allergic reactions to drugs or foods, nonionic contrast media should be used. In addition, consider administering prednisone 50 mg PO (or equivalent dose of other steroids) 13 hours, 7 hours, and 1 hour prior to the exam or procedure plus diphenhydramine 50 mg IM/PO one hour prior to the procedure. The administration of prophylactic steroids and antihistamines does not prevent all hypersensitivity reactions, but reduces the likelihood and may decrease the severity of the reaction.
NOTE: Only the lowest dose of iohexol necessary to obtain adequate visualization should be used. Using lower doses reduces the risk of adverse reactions. The dose and concentration of iohexol, age of the patient, patient's body size, size of the vessel and its blood flow, pathology and degree and extent of opacification required, area to be examined, the patient's disease states, and technique to be employed should all be considered when determining the necessary dose.
For use in angiography via intravascular administration:
-for use as a contrast in cerebral arteriography:
Intra-arterial dosage:
Adults: 6 to 12 mL of iohexol 300 mg iodine/mL (Omnipaque 300) for visualization of the common carotid artery, 8 to 10 mL of iohexol 300 mg iodine/mL (Omnipaque 300) for visualization of the internal carotid artery, 6 to 9 mL of iohexol 300 mg iodine/mL (Omnipaque 300) for visualization of the external carotid artery, and 6 to 10 mL of iohexol 300 mg iodine/mL (Omnipaque 300) for visualization of the vertebral artery.
-for use as a contrast in peripheral arteriography:
Intra-arterial dosage:
Adults: 20 to 70 mL of iohexol 350 mg iodine/mL (Omnipaque 350) or 30 to 90 mL of iohexol 300 mg iodine/mL (Omnipaque 300) for aortofemoral runoffs can be used; for selective arteriograms (femoral or iliac), 10 to 30 mL of iohexol 350 mg iodine/mL (Omnipaque 350) or 10 to 60 mL of iohexol 300 mg iodine/mL (Omnipaque 300) can be used.
-for use as a contrast in peripheral venography (phlebography):
Intravenous dosage:
Adults: 20 to 150 mL of iohexol 240 mg iodine/mL (Omnipaque 240) or 40 to 100 mL iohexol 300 mg iodine/mL (Omnipaque 300) per leg to be visualized can be used. After the procedure, flush the venous system with normal saline or 5% Dextrose Injection. Massage and elevation of the affected limb may help in clearing the contrast medium from the extremity.
-for use as a contrast in selective visceral arteriography and aortography:
Intra-arterial dosage:
NOTE: When using large volumes as a single injection (i.e., during ventriculography or aortography), several minutes between repeat injections should lapse to allow for correction of hemodynamic disturbances.
Adults: 50 to 80 mL of iohexol 300 mg iodine/mL (Omnipaque 300) or iohexol 350 mg iodine/mL (Omnipaque 350) for larger vessels, such as the aorta (aortic arch or ascending aorta); 30 to 60 mL of iohexol 300 mg iodine/mL (Omnipaque 300) or iohexol 350 mg iodine/mL (Omnipaque 350) for abdominal aorta and its major branches (i.e., celiac, mesenteric, hepatic, and splenic arteries); 5 to 15 mL of iohexol 300 mg iodine/mL (Omnipaque 300) or iohexol 350 mg iodine/mL (Omnipaque 350) for renal arteries. If repeated injections are required, do not exceed 87.5 mg of iodine, which is equivalent to 290 mL of iohexol 300 mg iodine/mL (Omnipaque 300) or 250 mL of iohexol 350 mg iodine/mL (Omnipaque 350).
Infants, Children, and Adolescents: 1 mL/kg of iohexol 350 mg iodine/mL (Omnipaque 350) for viewing aortic root, aortic arch, and descending aorta. If repeated injections are required, up to 5 mL/kg and a volume of 250 mL can be used.
-for use as a contrast in adult angiocardiography including ventriculography and coronary arteriography:
Intra-arterial dosage:
Adults: 40 mL (range 30 to 60 mL) of iohexol 350 mg iodine/mL (Omnipaque 350) for ventriculography or 5 mL (range 3 to 14 mL) of iohexol 350 mg iodine/mL (Omnipaque 350) for right or left coronary arteriography. Multiple vascular systems and organs can be visualized during a single radiographic examination. The maximum dosage for multiple procedures is 87.5 g of iodine or 250 mL of iohexol 350 mg iodine/mL (Omnipaque 350). ECGs and vital signs should be routinely monitored during this procedure.
-for use as a contrast during pediatric angiocardiography:
Intra-arterial dosage:
Infants, Children, and Adolescents: For ventriculography, the usual single injection dosage is 1.25 mL/kg of body weight (range 1 to 1.5 mL/kg) of iohexol 350 mg iodine/mL (Omnipaque 350). Alternatively, 1.75 mL/kg of body weight (range 1.5 to 2 mL/kg) of iohexol 300 mg iodine/mL (Omnipaque 300) can be used. For pulmonary angiography, the usual single injection dosage is 1 mL/kg of iohexol 350 mg iodine/mL (Omnipaque 350). If multiple injections are given or visualization of multiple vascular systems and organs are desired during a single procedure, the total dose should not exceed 5 mL/kg up to a total volume of 250 mL of iohexol 350 mg iodine/mL (Omnipaque 350) or 6 mL/kg up to a total volume of 291 mL of iohexol 300 mg iodine/mL (Omnipaque 300). NOTE: When using large volumes as a single injection, several minutes between repeat injections should lapse to allow for correction of hemodynamic disturbances. ECGs and vital signs should be routinely monitored during this procedure.
-for use as a contrast in digital subtraction angiography (DSA):
NOTE: Mechanical or hand injections can be used to administer one or more bolus intra-arterial and intravenous injections. The volume and rate of injection will depend on the type of equipment, technique used, and the vascular areas to be visualized.
Intra-arterial dosage:
Adults: 20 to 45 mL of iohexol 140 mg iodine/mL (Omnipaque 140) at a rate of 8 to 20 mL/second for visualization of the aorta; 8 to 25 mL of iohexol 140 mg iodine/mL (Omnipaque 140) at a rate of 3 to 10 mL/second for visualization of the other branches of the aorta (subclavian, axillary, innominate, iliac arteries); 5 to 10 mL of iohexol 140 mg iodine/mL (Omnipaque 140) at a rate of 3 to 6 mL/second for visualization of the carotid arteries; 9 to 20 mL of iohexol 140 mg iodine/mL (Omnipaque 140) at a rate of 3 to 6 mL/second for visualization of the femoral artery; 4 to 10 mL of iohexol 140 mg iodine/mL (Omnipaque 140) at a rate of 2 to 8 mL/second for visualization of the vertebral arteries; and 6 to 12 mL of iohexol 140 mg iodine/mL (Omnipaque 140) at a rate of 3 to 6 mL/second For visualization of the renal arteries.
Intravenous dosage:
Adults: 30 to 50 mL of iohexol 350 mg iodine/mL (Omnipaque 350) IV per injection at 7.5 to 30 mL/second using a pressure injector. Usually, 3 or more injections are required up to a total volume of 250 mL.
For use as contrast enhancement during computed tomography (CT) imaging of the head, body, or abdomen:
-for use as contrast enhancement during CT imaging of the head:
Intravenous dosage:
Adults: 70 to 150 mL of iohexol 300 mg iodine/mL (Omnipaque 300) or 80 mL of 350 mg iodine/mL (Omnipaque 350) via rapid IV injection. Alternatively, 120 to 150 mL of iohexol 240 mg iodine/mL (Omnipaque 240) via IV infusion.
Infants, Children, and Adolescents: 1 to 2 mL/kg of iohexol 240 mg iodine/mL (Omnipaque 240) or 300 mg iodine/mL (Omnipaque 300) via rapid IV injection. The maximum single dose is 3 mL/kg [Max: 116 mL; 28 g of iodine of iohexol 240 mg iodine/mL (Omnipaque 240) or 35 g of iodine of iohexol 300 mg iodine/mL (Omnipaque 300)].
Neonates: 1 to 2 mL/kg of iohexol 300 mg iodine/mL (Omnipaque 300) via rapid IV injection. The maximum single dose is 3 mL/kg.
-for use as contrast enhancement during CT imaging of the body:
Intravenous dosage:
Adults: 50 to 200 mL of iohexol 300 mg iodine/mL (Omnipaque 300) or 60 to 100 mL of iohexol 350 mg iodine/mL (Omnipaque 350) via rapid IV injection.
Infants, Children, and Adolescents: 1 to 2 mL/kg of iohexol 240 mg iodine/mL (Omnipaque 240) or 300 mg iodine/mL (Omnipaque 300) via rapid IV injection. The maximum single dose is 3 mL/kg [Max: 116 mL; 28 g of iodine of iohexol 240 mg iodine/mL (Omnipaque 240) or 35 g of iodine of iohexol 300 mg iodine/mL (Omnipaque 300)].
Neonates: 1 to 2 mL/kg of iohexol 300 mg iodine/mL (Omnipaque 300) via rapid IV injection. The maximum single dose is 3 mL/kg.
-for use in contrast enhanced computed tomography of the abdomen/GI tract:
NOTE: Dilute oral plus intravenous iohexol injection may be useful when unenhanced imaging does not provide sufficient delineation between normal loops of bowel and adjacent organs or areas of suspected pathology.
Oral dosage:
Adults: 500 to 1,000 mL PO of iohexol 9 or 12 mg iodine/mL (Omnipaque oral solution 9 or 12) or diluted iohexol injection (Omnipaque 240, 300, or 350) at 6 to 12 mg iodine/mL in conjunction with IV iohexol. May give oral dosage all at once or over a period of 45 minutes.
Children and Adolescents 3 to 17 years: 180 to 750 mL PO of iohexol 9 or 12 mg iodine/mL (Omnipaque oral solution 9 or 12) or diluted iohexol injection (Omnipaque 240, 300, or 350) at 9 to 21 mg iodine/mL in conjunction with IV iohexol. Do not exceed 10 g of iodine PO. May give oral dosage all at once or over a period of 45 minutes.
Infants and Children 1 to 2 years: 180 to 750 mL PO of iohexol 9 or 12 mg iodine/mL (Omnipaque oral solution 9 or 12) or diluted iohexol injection (Omnipaque 240, 300, or 350) at 9 to 21 mg iodine/mL in conjunction with IV iohexol. Do not exceed 5 g of iodine PO. May give oral dosage all at once or over a period of 45 minutes.
Intravenous dosage:
Adults: 100 to 150 mL of iohexol 300 mg iodine/mL (Omnipaque 300) IV in conjunction with PO iohexol. May administer IV up to 40 minutes after the oral dose.
Infants, Children, and Adolescents: 1 to 2 mL/kg of iohexol 240 mg iodine/mL (Omnipaque 240) or 300 mg iodine/mL (Omnipaque 300) IV in conjunction with PO iohexol. Do not exceed 3 mL/kg IV. May administer IV up to 60 minutes after the oral dose.
For use as a contrast in excretory urography:
NOTE: Because temporary suppression of urine formation is possible, it is recommended that a suitable interval lapse before excretory urography is repeated.
Intravenous dosage:
Adults: 0.6 to 1.2 mL/kg of iohexol 300 mg iodine/mL (Omnipaque 300) or iohexol 350 mg iodine/mL (Omnipaque 350) is indicated IV.
Infants, Children, and Adolescents: 0.5 to 3 mL/kg of iohexol 300 mg iodine/mL (Omnipaque 300) IV. The usual dosage for children is 1 to 1.5 mL/kg. Dosages for infants and children should be administered in proportion to body weight. The total administered dose should not exceed 3 mL/kg.
-for use during voiding cystourethrography (VCU):
NOTE: VCU is often performed in conjunction with excretory urography.
Intravesical dosage:
Infants, Children, and Adolescents: 50 to 300 mL of diluted iohexol injection (Omnipaque 240, 300, or 350) at 100 mg iodine/mL or 50 to 600 mL of diluted iohexol injection (Omnipaque 240, 300, or 350) at 50 mg iodine/mL. Sufficient volume should be instilled so that the bladder is filled.
For oral pass-through radiographic examination of the gastrointestinal (GI) tract (gastrointestinal radiography):
NOTE: Iohexol is useful in this indication when barium is contraindicated as in those patients with suspected bowel perforation or when aspiration of the contrast medium is a possibility.
Oral dosage:
Adults: 50 to 100 mL PO of undiluted iohexol injection 350 mg iodine/mL (Omnipaque 350).
Children 11 to 12 years and Adolescents: Up to 100 mL PO of undiluted iohexol injection 180 mg iodine/mL (Omnipaque 180), 240 mg iodine/mL (Omnipaque 240), or 300 mg iodine/mL (Omnipaque 300).
Children 4 to 10 years: Up to 80 mL PO of undiluted iohexol injection 180 mg iodine/mL (Omnipaque 180), 240 mg iodine/mL (Omnipaque 240), or 300 mg iodine/mL (Omnipaque 300).
Infants 3 to 11 months and Children 1 to 3 years: Up to 60 mL PO of undiluted iohexol injection 180 mg iodine/mL (Omnipaque 180), 240 mg iodine/mL (Omnipaque 240), or 300 mg iodine/mL (Omnipaque 300).
Infants younger than 3 months: 5 to 30 mL PO of undiluted iohexol injection 180 mg iodine/mL (Omnipaque 180).
Rectal dosage:
Children 11 to 12 years and Adolescents: Up to 100 mL PR of undiluted iohexol injection 180 mg iodine/mL (Omnipaque 180), 240 mg iodine/mL (Omnipaque 240), or 300 mg iodine/mL (Omnipaque 300). When given rectally, larger volumes may be used.
Children 4 to 10 years: Up to 80 mL PR of undiluted iohexol injection 180 mg iodine/mL (Omnipaque 180), 240 mg iodine/mL (Omnipaque 240), or 300 mg iodine/mL (Omnipaque 300). When given rectally, larger volumes may be used.
Infants 3 to 11 months and Children 1 to 3 years: Up to 60 mL PR of undiluted iohexol injection 180 mg iodine/mL (Omnipaque 180), 240 mg iodine/mL (Omnipaque 240), or 300 mg iodine/mL (Omnipaque 300). When given rectally, larger volumes may be used.
Infants younger than 3 months: 5 to 30 mL PR of undiluted iohexol injection 180 mg iodine/mL (Omnipaque 180). When given rectally, larger volumes may be used.
For use during endoscopic retrograde pancreatography (ERP) or endoscopic retrograde cholangiopancreatography (ERCP):
Intraductal dosage:
Adults: 10 to 50 mL of iohexol 240 mg iodine/mL (Omnipaque 240). The dosage may vary depending on individual anatomy and/or disease state.
For use as a contrast during hysterosalpingography:
Intrauterine dosage:
Adult females: 15 to 20 mL of iohexol 240 mg iodine/mL (Omnipaque 240) or 300 mg iodine/mL (Omnipaque 300). Individual dosages may vary depending on the patient's anatomy and and/or disease state.
For use as a contrast during herniography:
Parenteral dosage:
Adults: 50 mL of iohexol 240 mg iodine/mL (Omnipaque 240); dosages may vary depending on individual anatomy and/or disease state.
For use as a contrast in arthrography:
NOTE: Arthrography is usually performed under local anesthesia. The dosages listed below are a guide as more or less contrast medium may be required for optimal visualization. In general, lower dosages are recommended for double-contrast examinations (using 15 to 100 mL of air); higher dosages are recommended for single-contrast examination. The contrast media can be dispersed through the joint space by passive or active manipulation.
Intra-articular dosage:
Adults: 5 to 15 mL of iohexol 240 mg iodine/mL (Omnipaque 240) or 300 mg iodine/mL (Omnipaque 300) for radiography of the knee. Alternatively, 5 to 10 mL of iohexol 350 mg iodine/mL (Omnipaque 350) can be used. For radiography of the shoulder, 3 mL of iohexol 240 mg iodine/mL (Omnipaque 240) or 10 mL of iohexol 300 mg iodine/mL (Omnipaque 300) is recommended. For radiography of the temporomandibular joint, 0.5 to 1 mL of iohexol 300 mg iodine/mL (Omnipaque 300) is recommended.
For use in neuroradiology including myelography:
NOTE: Only iohexol 180 mg iodine/mL (Omnipaque 180), 240 mg iodine/mL (Omnipaque 240), or 300 mg iodine/mL (Omnipaque 300) should be used intrathecally.
NOTE: Per the manufacturer, neuroleptic drugs (including phenothiazines) should be held for at least 48 hours before and for at least 24 hours after the procedure. NOTE: A minimum interval of 48 hours should pass between repeat examinations; however, 5 to 7 days between examinations is preferable when possible. Only one injection of iohexol should be given per procedure when used intrathecally.
NOTE: The pediatric dosages listed are based on age rather than weight because the brain and CSF volume are independent of weight. However, dosage may vary based on individual factors such as patient height, suspected pathology, patient condition, and technique.
NOTE: The following recommended dosages apply whether conventional myelography or contrast enhanced computerized tomography is used.
-for use as a contrast in lumbar myelography (via lumbar injection):
Intrathecal dosage:
Adults: 10 to 17 mL of iohexol 180 mg iodine/mL (Omnipaque 180). Alternatively, 7 to 12.5 mL of iohexol 240 mg iodine/mL (Omnipaque 240) can be used.
Adolescents: 6 to 15 mL of iohexol 180 mg iodine/mL (Omnipaque 180).
Children 7 to 12 years: 5 to 12 mL of iohexol 180 mg iodine/mL (Omnipaque 180).
Children 3 to 6 years: 5 to 10 mL of iohexol 180 mg iodine/mL (Omnipaque 180).
Infants and Children 3 months to 2 years: 4 to 8 mL of iohexol 180 mg iodine/mL (Omnipaque 180).
Neonates and Infants 1 to 2 months: 2 to 4 mL of iohexol 180 mg iodine/mL (Omnipaque 180).
-for use as a contrast in thoracic myelography (via lumbar or cervical injection):
NOTE: Only thoracic myelography via lumbar puncture is indicated for pediatric patients.
Intrathecal dosage:
Adults: 6 to 12.5 mL of iohexol 240 mg iodine/mL (Omnipaque 240). Alternatively, 6 to 10 mL of iohexol 300 mg iodine/mL (Omnipaque 300) can be used.
Adolescents: 6 to 15 mL of iohexol 180 mg iodine/mL (Omnipaque 180).
Children 7 to 12 years: 5 to 12 mL of iohexol 180 mg iodine/mL (Omnipaque 180).
Children 3 to 6 years: 5 to 10 mL of iohexol 180 mg iodine/mL (Omnipaque 180).
Infants and Children 3 months to 2 years: 4 to 8 mL of iohexol 180 mg iodine/mL (Omnipaque 180).
Neonates and Infants 1 to 2 months: 2 to 4 mL of iohexol 180 mg iodine/mL (Omnipaque 180).
-for use as a contrast in cervical myelography (via lumbar injection):
Intrathecal dosage:
Adults: 6 to 12.5 mL of iohexol 240 mg iodine/mL (Omnipaque 240). Alternatively, 6 to 10 mL of iohexol 300 mg iodine/mL (Omnipaque 300) can be used.
Adolescents: 6 to 15 mL of iohexol 180 mg iodine/mL (Omnipaque 180).
Children 7 to 12 years: 5 to 12 mL of iohexol 180 mg iodine/mL (Omnipaque 180).
Children 3 to 6 years: 5 to 10 mL of iohexol 180 mg iodine/mL (Omnipaque 180).
Infants and Children 3 months to 2 years: 4 to 8 mL of iohexol 180 mg iodine/mL (Omnipaque 180).
Neonates and Infants 1 to 2 months: 2 to 4 mL of iohexol 180 mg iodine/mL (Omnipaque 180).
-for use as a contrast in cervical myelography (via C1 to C2 injection):
Intrathecal dosage:
Adults: 7 to 10 mL of iohexol 180 mg iodine/mL (Omnipaque 180) can be used. Alternatively, 6 to 12.5 mL of iohexol 240 mg iodine/mL (Omnipaque 240) or 4 to 10 mL of iohexol 300 mg iodine/mL (Omnipaque 300) can be used.
-for use as a contrast in total columnar myelography (via lumbar injection):
Intrathecal dosage:
Adults: 6 to 12.5 mL of iohexol 240 mg iodine/mL (Omnipaque 240). Alternatively, 6 to 10 mL of iohexol 300 mg iodine/mL (Omnipaque 300) can be used.
Adolescents: 6 to 15 mL of iohexol 180 mg iodine/mL (Omnipaque 180).
Children 7 to 12 years: 5 to 12 mL of iohexol 180 mg iodine/mL (Omnipaque 180).
Children 3 to 6 years: 5 to 10 mL of iohexol 180 mg iodine/mL (Omnipaque 180).
Infants and Children 3 months to 2 years: 4 to 8 mL of iohexol 180 mg iodine/mL (Omnipaque 180).
Neonates and Infants 1 to 2 months: 2 to 4 mL of iohexol 180 mg iodine/mL (Omnipaque 180).
Maximum Dosage Limits:
-Adults
Do not exceed recommended volume or concentration for the particular indication; 87.5 grams iodine (250 mL of 350 mg iodine/mL or 291 mL of 300 mg iodine/mL) via intravascular administration; 3.06 grams iodine and a concentration of 300 mg iodine/mL via intrathecal administration.
-Geriatric
Do not exceed recommended volume or concentration for the particular indication; 87.5 grams iodine (250 mL of 350 mg iodine/mL or 291 mL of 300 mg iodine/mL) via intravascular administration; 3.06 grams iodine and a concentration of 300 mg iodine/mL via intrathecal administration.
-Adolescents
Do not exceed the recommended volume or concentration for the particular indication; 87.5 grams of iodine (5 mL/kg or 250 mL of 350 mg iodine/mL or 6 mL/kg or 291 mL of 300 mg iodine/mL) via intravascular administration; 2.7 grams iodine (15 mL) of 180 mg iodine/mL via intrathecal administration.
-Children
7 to 12 years: Do not exceed the recommended volume or concentration for the particular indication; 87.5 g of iodine (5 mL/kg or 250 mL of 350 mg iodine/mL or 6 mL/kg or 291 mL of 300 mg iodine/mL) via intravascular administration; 2.16 g of iodine (12 mL) of 180 mg iodine/mL via intrathecal administration.
3 to 6 years: Do not exceed the recommended volume or concentration for the particular indication; 5 mL/kg of 350 mg iodine/mL or 6 mL/kg of 300 mg iodine/mL) via intravascular administration; 1.8 g of iodine (10 mL) of 180 mg iodine/mL via intrathecal administration.
1 to 2 years: Do not exceed the recommended volume or concentration for the particular indication; 5 mL/kg of 350 mg iodine/mL or 6 mL/kg of 300 mg iodine/mL) via intravascular administration; 1.44 g of iodine (8 mL) of 180 mg iodine/mL via intrathecal administration.
-Infants
3 to 11 months: Do not exceed the recommended volume or concentration for the particular indication; 5 mL/kg of 350 mg iodine/mL or 6 mL/kg of 300 mg iodine/mL) via intravascular administration; 1.44 g of iodine (8 mL) of 180 mg iodine/mL via intrathecal administration.
1 to 2 months: Do not exceed the recommended volume or concentration for the particular indication; 5 mL/kg of 350 mg iodine/mL or 6 mL/kg of 300 mg iodine/mL) via intravascular administration; 0.72 g of iodine (4 mL) of 180 mg iodine/mL via intrathecal administration.
-Neonates
Do not exceed the recommended volume or concentration for the particular indication; 3 mL/kg of 300 mg iodine/mL via intravascular administration; 0.72 g of iodine (4 mL) of 180 mg iodine/mL via intrathecal administration.
Patients with Hepatic Impairment Dosing
Specific guidelines for dosage adjustment in hepatic impairment are not available; it appears no dosage adjustments are needed.
Patients with Renal Impairment Dosing
Specific guidelines for dosage adjustment in renal impairment are not available; however, iohexol can cause acute renal failure and this risk is higher in patients with underlying renal insufficiency. Patients with renal insufficiency should be well-hydrated and the smallest volume of contrast media should be used.
*non-FDA-approved indication
Acebutolol: (Moderate) Use caution when administering non-ionic contrast media to patients taking beta-blockers. Beta-blockers lower the threshold for and increase the severity of contrast reactions and reduce the responsiveness of treatment of hypersensitivity reactions with epinephrine.
Acetaminophen; Aspirin, ASA; Caffeine: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering intrathecal radiopaque contrast agents. Caffeine and caffeine containing products should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours post-procedure.
Acetaminophen; Caffeine: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering intrathecal radiopaque contrast agents. Caffeine and caffeine containing products should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours post-procedure.
Acetaminophen; Caffeine; Dihydrocodeine: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering intrathecal radiopaque contrast agents. Caffeine and caffeine containing products should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours post-procedure.
Acetaminophen; Caffeine; Pyrilamine: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering intrathecal radiopaque contrast agents. Caffeine and caffeine containing products should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours post-procedure.
Acetaminophen; Chlorpheniramine; Dextromethorphan; Phenylephrine: (Major) Do not administer non-ionic contrast media intra-arterially after the administration of vasopressors since they strongly potentiate neurologic effects.
Acetaminophen; Chlorpheniramine; Phenylephrine : (Major) Do not administer non-ionic contrast media intra-arterially after the administration of vasopressors since they strongly potentiate neurologic effects.
Acetaminophen; Dextromethorphan; Guaifenesin; Phenylephrine: (Major) Do not administer non-ionic contrast media intra-arterially after the administration of vasopressors since they strongly potentiate neurologic effects.
Acetaminophen; Dextromethorphan; Phenylephrine: (Major) Do not administer non-ionic contrast media intra-arterially after the administration of vasopressors since they strongly potentiate neurologic effects.
Acetaminophen; Guaifenesin; Phenylephrine: (Major) Do not administer non-ionic contrast media intra-arterially after the administration of vasopressors since they strongly potentiate neurologic effects.
Acetaminophen; Ibuprofen: (Moderate) Nonsteroidal anti-inflammatory drugs (NSAIDs) may increase the risk for nephrotoxicity when given to patients receiving a contrast agents. When possible, withhold NSAID therapy during administration of a contrast agent.
Acetaminophen; Phenylephrine: (Major) Do not administer non-ionic contrast media intra-arterially after the administration of vasopressors since they strongly potentiate neurologic effects.
Acyclovir: (Moderate) Concomitant use of acyclovir and contrast agents should be avoided when possible, as use of these drugs together may increase the risk for nephrotoxicity.
Aldesleukin, IL-2: (Moderate) Monitor patients for delayed aldesleukin "recall" reactions in patients receiving iodinated contrast media after aldesleukin therapy. Symptom onset is typically from 1 to 4 hours after administration of iodinated contrast media and may resemble aldesleukin-related infusion reactions including fever, chills, nausea, vomiting, pruritus, rash, diarrhea, hypotension, edema, and oliguria. While most common when contrast media is given within 4 weeks of the last dose of aldesleukin, reports have also occurred when contrast media was administered several months after aldesleukin treatment.
Aliskiren; Hydrochlorothiazide, HCTZ: (Major) Do not use diuretics before non-ionic contrast media administration. Concomitant use of diuretics and non-ionic contrast media may increase the risk for acute kidney injury, including renal failure.
Alogliptin; Metformin: (Major) Discontinue metformin at the time of, or before, administration of non-ionic contrast media to patients with an eGFR of 30 to 60 mL/minute/1.73 m2, history of liver disease, alcoholism, or heart failure, or who will be administered intra-arterial iodinated contrast. Reevaluate eGFR 48 hours after the imaging procedure; restart metformin if renal function is stable. Iodinated contrast agents appear to increase the risk of metformin-induced lactic acidosis, possibly as a result of worsening renal function.
Amikacin: (Moderate) Because the use of other nephrotoxic drugs, such as aminoglycoside antibiotics, is an additive risk factor for nephrotoxicity in patients receiving radiopaque contrast agents, concomitant use should be avoided when possible.
Amiloride: (Major) Do not use diuretics before non-ionic contrast media administration. Concomitant use of diuretics and non-ionic contrast media may increase the risk for acute kidney injury, including renal failure.
Amiloride; Hydrochlorothiazide, HCTZ: (Major) Do not use diuretics before non-ionic contrast media administration. Concomitant use of diuretics and non-ionic contrast media may increase the risk for acute kidney injury, including renal failure.
Aminoglycosides: (Moderate) Because the use of other nephrotoxic drugs, such as aminoglycoside antibiotics, is an additive risk factor for nephrotoxicity in patients receiving radiopaque contrast agents, concomitant use should be avoided when possible.
Amiodarone: (Major) When injected directly into coronary arteries, contrast media can cause bradycardia and QT interval prolongation; these reactions tend to be less common with nonionic low-osmolar contrast media. In a retrospective review of 21 patients on amiodarone therapy who underwent cardiac catheterization with iohexol, the QTc interval was significantly prolonged 12-24 hours post catheterization from a baseline QTc interval of 433 msec (95%CI 419-483 msec) to 480 msec (95%CI, 422-483 msec) (p< 0.001). No significant change in the QTc interval was seen in non-amiodarone treated control patients. Until more data are available, clinicians should closely monitor patients taking amiodarone during cardiac catheterization with radiopaque contrast agents; EKG monitoring during intra-coronary artery injection of radiopaque contrast agents is recommended.
Amitriptyline: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering the use of intrathecal radiopaque contrast agents. Tricyclic antidepressants should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Amlodipine; Benazepril: (Moderate) Because the use of other nephrotoxic drugs, including ACE inhibitors, is an additive risk factor for nephrotoxicity in patients receiving radiopaque contrast agents, ACE inhibitor therapy should be withheld, when possible, during radiopaque contrast agent administration.
Amlodipine; Celecoxib: (Moderate) Nonsteroidal anti-inflammatory drugs (NSAIDs) may increase the risk for nephrotoxicity when given to patients receiving a contrast agents. When possible, withhold NSAID therapy during administration of a contrast agent.
Amlodipine; Valsartan; Hydrochlorothiazide, HCTZ: (Major) Do not use diuretics before non-ionic contrast media administration. Concomitant use of diuretics and non-ionic contrast media may increase the risk for acute kidney injury, including renal failure.
Amoxapine: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering the use of intrathecal radiopaque contrast agents. Amoxapine should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Amphetamine: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering the use of intrathecal radiopaque contrast agents. Amphetamines should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Amphetamine; Dextroamphetamine Salts: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering the use of intrathecal radiopaque contrast agents. Amphetamines should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Amphetamine; Dextroamphetamine: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering the use of intrathecal radiopaque contrast agents. Amphetamines should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Amphotericin B: (Moderate) Because the use of other nephrotoxic drugs, including amphotericin B, is an additive risk factor for nephrotoxicity in patients receiving radiopaque contrast agents, concomitant use should be avoided when possible.
Angiotensin II: (Major) Do not administer non-ionic contrast media intra-arterially after the administration of vasopressors since they strongly potentiate neurologic effects.
Angiotensin-converting enzyme inhibitors: (Moderate) Because the use of other nephrotoxic drugs, including ACE inhibitors, is an additive risk factor for nephrotoxicity in patients receiving radiopaque contrast agents, ACE inhibitor therapy should be withheld, when possible, during radiopaque contrast agent administration.
Aprotinin: (Moderate) The manufacturer recommends using aprotinin cautiously in patients that are receiving drugs that can affect renal function, such as radiopaque contrast agents, as the risk of renal impairment may be increased.
Aripiprazole: (Major) Aripiprazole lowers the seizure threshold and should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Articaine; Epinephrine: (Major) Do not administer non-ionic contrast media intra-arterially after the administration of vasopressors since they strongly potentiate neurologic effects.
Asenapine: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering intrathecal radiopaque contrast agents. Antipsychotics should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours post-procedure. The frequency of seizure activity with asenapine was low during clinical trials; however, seizures have been associated with other antipsychotics and caution is advised.
Aspirin, ASA; Butalbital; Caffeine: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering intrathecal radiopaque contrast agents. Caffeine and caffeine containing products should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours post-procedure.
Aspirin, ASA; Caffeine: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering intrathecal radiopaque contrast agents. Caffeine and caffeine containing products should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours post-procedure.
Aspirin, ASA; Caffeine; Orphenadrine: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering intrathecal radiopaque contrast agents. Caffeine and caffeine containing products should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours post-procedure.
Atenolol: (Moderate) Use caution when administering non-ionic contrast media to patients taking beta-blockers. Beta-blockers lower the threshold for and increase the severity of contrast reactions and reduce the responsiveness of treatment of hypersensitivity reactions with epinephrine.
Atenolol; Chlorthalidone: (Major) Do not use diuretics before non-ionic contrast media administration. Concomitant use of diuretics and non-ionic contrast media may increase the risk for acute kidney injury, including renal failure. (Moderate) Use caution when administering non-ionic contrast media to patients taking beta-blockers. Beta-blockers lower the threshold for and increase the severity of contrast reactions and reduce the responsiveness of treatment of hypersensitivity reactions with epinephrine.
Azilsartan; Chlorthalidone: (Major) Do not use diuretics before non-ionic contrast media administration. Concomitant use of diuretics and non-ionic contrast media may increase the risk for acute kidney injury, including renal failure.
Barium Sulfate: (Major) Delay the administration of non-ionic contrast media in patients who have recently received an oral cholecystographic contrast agent, such as barium. Renal toxicity has been reported in patients with liver dysfunction who were given an oral cholecystographic agent followed by intravascular iodinated contrast agents.
Benazepril: (Moderate) Because the use of other nephrotoxic drugs, including ACE inhibitors, is an additive risk factor for nephrotoxicity in patients receiving radiopaque contrast agents, ACE inhibitor therapy should be withheld, when possible, during radiopaque contrast agent administration.
Benazepril; Hydrochlorothiazide, HCTZ: (Major) Do not use diuretics before non-ionic contrast media administration. Concomitant use of diuretics and non-ionic contrast media may increase the risk for acute kidney injury, including renal failure. (Moderate) Because the use of other nephrotoxic drugs, including ACE inhibitors, is an additive risk factor for nephrotoxicity in patients receiving radiopaque contrast agents, ACE inhibitor therapy should be withheld, when possible, during radiopaque contrast agent administration.
Benzphetamine: (Major) Sympathomimetics lower the seizure threshold and should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Beta-blockers: (Moderate) Use caution when administering non-ionic contrast media to patients taking beta-blockers. Beta-blockers lower the threshold for and increase the severity of contrast reactions and reduce the responsiveness of treatment of hypersensitivity reactions with epinephrine.
Betamethasone: (Major) Serious adverse events, including death, have been observed during intrathecal administration of both corticosteroids (i.e., betamethasone) and radiopaque contrast agents (i.e., iohexol); therefore, concurrent use of these medications via the intrathecal route is contraindicated. Cases of cortical blindness, stroke, spinal cord infarction, paralysis, seizures, nerve injury, brain edema, and death have been temporally associated (i.e., within minutes to 48 hours after injection) with epidural administration of injectable corticosteroids. In addition, patients inadvertently administered iohexol formulations not indicated for intrathecal use have experienced seizures, convulsions, cerebral hemorrhages, brain edema, and death. Administering these medications together via the intrathecal route may increase the risk for serious adverse events.
Betaxolol: (Moderate) Use caution when administering non-ionic contrast media to patients taking beta-blockers. Beta-blockers lower the threshold for and increase the severity of contrast reactions and reduce the responsiveness of treatment of hypersensitivity reactions with epinephrine.
Bictegravir; Emtricitabine; Tenofovir Alafenamide: (Moderate) Monitor for changes in renal function if tenofovir alafenamide is administered in combination with nephrotoxic agents, such as radiopaque contrast agents. Tenofovir is primarily excreted via the kidneys by a combination of glomerular filtration and active tubular secretion. Coadministration of tenofovir alafenamide with a drug that reduces renal function or competes for active tubular secretion may increase concentrations of tenofovir and other renally eliminated drugs; thus, increasing the risk of developing renal-related adverse reactions.
Bisoprolol: (Moderate) Use caution when administering non-ionic contrast media to patients taking beta-blockers. Beta-blockers lower the threshold for and increase the severity of contrast reactions and reduce the responsiveness of treatment of hypersensitivity reactions with epinephrine.
Bisoprolol; Hydrochlorothiazide, HCTZ: (Major) Do not use diuretics before non-ionic contrast media administration. Concomitant use of diuretics and non-ionic contrast media may increase the risk for acute kidney injury, including renal failure. (Moderate) Use caution when administering non-ionic contrast media to patients taking beta-blockers. Beta-blockers lower the threshold for and increase the severity of contrast reactions and reduce the responsiveness of treatment of hypersensitivity reactions with epinephrine.
Brexpiprazole: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering intrathecal radiopaque contrast agents. Antipsychotics such as brexpiprazole should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours post procedure.
Brimonidine; Timolol: (Moderate) Use caution when administering non-ionic contrast media to patients taking beta-blockers. Beta-blockers lower the threshold for and increase the severity of contrast reactions and reduce the responsiveness of treatment of hypersensitivity reactions with epinephrine.
Brompheniramine; Dextromethorphan; Phenylephrine: (Major) Do not administer non-ionic contrast media intra-arterially after the administration of vasopressors since they strongly potentiate neurologic effects.
Brompheniramine; Phenylephrine: (Major) Do not administer non-ionic contrast media intra-arterially after the administration of vasopressors since they strongly potentiate neurologic effects.
Bumetanide: (Major) Do not use diuretics before non-ionic contrast media administration. Concomitant use of diuretics and non-ionic contrast media may increase the risk for acute kidney injury, including renal failure.
Bupivacaine; Epinephrine: (Major) Do not administer non-ionic contrast media intra-arterially after the administration of vasopressors since they strongly potentiate neurologic effects.
Bupivacaine; Meloxicam: (Moderate) Nonsteroidal anti-inflammatory drugs (NSAIDs) may increase the risk for nephrotoxicity when given to patients receiving a contrast agents. When possible, withhold NSAID therapy during administration of a contrast agent.
Bupropion: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering intrathecal radiopaque contrast agents. Bupropion should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Bupropion; Naltrexone: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering intrathecal radiopaque contrast agents. Bupropion should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Butalbital; Acetaminophen; Caffeine: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering intrathecal radiopaque contrast agents. Caffeine and caffeine containing products should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours post-procedure.
Butalbital; Acetaminophen; Caffeine; Codeine: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering intrathecal radiopaque contrast agents. Caffeine and caffeine containing products should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours post-procedure.
Butalbital; Aspirin; Caffeine; Codeine: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering intrathecal radiopaque contrast agents. Caffeine and caffeine containing products should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours post-procedure.
Caffeine: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering intrathecal radiopaque contrast agents. Caffeine and caffeine containing products should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure. (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering intrathecal radiopaque contrast agents. Caffeine and caffeine containing products should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours post-procedure.
Caffeine; Sodium Benzoate: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering intrathecal radiopaque contrast agents. Caffeine and caffeine containing products should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours post-procedure.
Calcium, Magnesium, Potassium, Sodium Oxybates: (Major) Sodium oxybate lowers seizure threshold and should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Canagliflozin; Metformin: (Major) Discontinue metformin at the time of, or before, administration of non-ionic contrast media to patients with an eGFR of 30 to 60 mL/minute/1.73 m2, history of liver disease, alcoholism, or heart failure, or who will be administered intra-arterial iodinated contrast. Reevaluate eGFR 48 hours after the imaging procedure; restart metformin if renal function is stable. Iodinated contrast agents appear to increase the risk of metformin-induced lactic acidosis, possibly as a result of worsening renal function.
Candesartan; Hydrochlorothiazide, HCTZ: (Major) Do not use diuretics before non-ionic contrast media administration. Concomitant use of diuretics and non-ionic contrast media may increase the risk for acute kidney injury, including renal failure.
Capreomycin: (Major) Because the use of other nephrotoxic drugs, including capreomycin, is an additive risk factor for nephrotoxicity in patients receiving radiopaque contrast agents, concomitant use should be avoided when possible. Monitor patients for changes in renal function if these drugs are coadministered.
Captopril: (Moderate) Because the use of other nephrotoxic drugs, including ACE inhibitors, is an additive risk factor for nephrotoxicity in patients receiving radiopaque contrast agents, ACE inhibitor therapy should be withheld, when possible, during radiopaque contrast agent administration.
Captopril; Hydrochlorothiazide, HCTZ: (Major) Do not use diuretics before non-ionic contrast media administration. Concomitant use of diuretics and non-ionic contrast media may increase the risk for acute kidney injury, including renal failure. (Moderate) Because the use of other nephrotoxic drugs, including ACE inhibitors, is an additive risk factor for nephrotoxicity in patients receiving radiopaque contrast agents, ACE inhibitor therapy should be withheld, when possible, during radiopaque contrast agent administration.
Carteolol: (Moderate) Use caution when administering non-ionic contrast media to patients taking beta-blockers. Beta-blockers lower the threshold for and increase the severity of contrast reactions and reduce the responsiveness of treatment of hypersensitivity reactions with epinephrine.
Carvedilol: (Moderate) Use caution when administering non-ionic contrast media to patients taking beta-blockers. Beta-blockers lower the threshold for and increase the severity of contrast reactions and reduce the responsiveness of treatment of hypersensitivity reactions with epinephrine.
Celecoxib: (Moderate) Nonsteroidal anti-inflammatory drugs (NSAIDs) may increase the risk for nephrotoxicity when given to patients receiving a contrast agents. When possible, withhold NSAID therapy during administration of a contrast agent.
Celecoxib; Tramadol: (Major) Tramadol lowers the seizure threshold and should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure. (Moderate) Nonsteroidal anti-inflammatory drugs (NSAIDs) may increase the risk for nephrotoxicity when given to patients receiving a contrast agents. When possible, withhold NSAID therapy during administration of a contrast agent.
Chlordiazepoxide; Amitriptyline: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering the use of intrathecal radiopaque contrast agents. Tricyclic antidepressants should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Chlorothiazide: (Major) Do not use diuretics before non-ionic contrast media administration. Concomitant use of diuretics and non-ionic contrast media may increase the risk for acute kidney injury, including renal failure.
Chlorpheniramine; Dextromethorphan; Phenylephrine: (Major) Do not administer non-ionic contrast media intra-arterially after the administration of vasopressors since they strongly potentiate neurologic effects.
Chlorpheniramine; Ibuprofen; Pseudoephedrine: (Moderate) Nonsteroidal anti-inflammatory drugs (NSAIDs) may increase the risk for nephrotoxicity when given to patients receiving a contrast agents. When possible, withhold NSAID therapy during administration of a contrast agent.
Chlorpheniramine; Phenylephrine: (Major) Do not administer non-ionic contrast media intra-arterially after the administration of vasopressors since they strongly potentiate neurologic effects.
Chlorpromazine: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering the use of intrathecal radiopaque contrast agents. Phenothiazines should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Chlorthalidone: (Major) Do not use diuretics before non-ionic contrast media administration. Concomitant use of diuretics and non-ionic contrast media may increase the risk for acute kidney injury, including renal failure.
Cisplatin: (Moderate) Closely monitor renal function if concomitant use with cisplatin and non-ionic contrast media is necessary. Both drugs can cause nephrotoxicity, which may be additive when used together.
Clindamycin: (Moderate) Concomitant use of non-ionic contrast media and clindamycin may result in additive nephrotoxicity. Monitor for renal toxicity if concomitant use is required.
Clomipramine: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering the use of intrathecal radiopaque contrast agents. Tricyclic antidepressants should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Clonazepam: (Moderate) The use of intrathecal radiopaque contrast agents is associated with a risk of seizures. Patients should be instructed to continue using benzodiazepines during procedures or exams that require the use of intrathecal radiopaque contrast agents as abrupt discontinuation of benzodiazepines may also increase seizure risk.
Clozapine: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering intrathecal radiopaque contrast agents. Antipsychotics should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Cocaine: (Major) Use of medications that lower the seizure threshold, such as cocaine, should be carefully evaluated when considering intrathecal radiopaque contrast agentsl. While the contributory role of such medications has not been established, some physicians discontinue these drugs at least 48 hours before and for at least 24 hours after intrathecal use.
Codeine; Phenylephrine; Promethazine: (Major) Do not administer non-ionic contrast media intra-arterially after the administration of vasopressors since they strongly potentiate neurologic effects. (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering the use of intrathecal radiopaque contrast agents. Phenothiazines should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Codeine; Promethazine: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering the use of intrathecal radiopaque contrast agents. Phenothiazines should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Colistimethate, Colistin, Polymyxin E: (Major) Because the use of other nephrotoxic drugs, including colistimethate sodium, is an additive risk factor for nephrotoxicity in patients receiving radiopaque contrast agents, concomitant use should be avoided when possible. Monitor patients for changes in renal function if these drugs are coadministered.
Colistin: (Major) Because the use of other nephrotoxic drugs, including colistimethate sodium, is an additive risk factor for nephrotoxicity in patients receiving radiopaque contrast agents, concomitant use should be avoided when possible. Monitor patients for changes in renal function if these drugs are coadministered.
Cortisone: (Major) Serious adverse events, including death, have been observed during intrathecal administration of both corticosteroids (i.e., cortisone) and radiopaque contrast agents (i.e., iohexol); therefore, concurrent use of these medications via the intrathecal route is contraindicated. Cases of cortical blindness, stroke, spinal cord infarction, paralysis, seizures, nerve injury, brain edema, and death have been temporally associated (i.e., within minutes to 48 hours after injection) with epidural administration of injectable corticosteroids. In addition, patients inadvertently administered iohexol formulations not indicated for intrathecal use have experienced seizures, convulsions, cerebral hemorrhages, brain edema, and death. Administering these medications together via the intrathecal route may increase the risk for serious adverse events.
Cyclobenzaprine: (Major) Use of medications that lower the seizure threshold, such as cyclobenzaprine, should be carefully evaluated when considering intrathecal radiopaque contrast agents. Cyclobenzaprine should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Cyclosporine: (Moderate) Because the use of other nephrotoxic drugs, including cyclosporine, is an additive risk factor for nephrotoxicity in patients receiving radiopaque contrast agents, when possible, cyclosporine should be withheld during radiopaque contrast agent administration.
Dapagliflozin; Metformin: (Major) Discontinue metformin at the time of, or before, administration of non-ionic contrast media to patients with an eGFR of 30 to 60 mL/minute/1.73 m2, history of liver disease, alcoholism, or heart failure, or who will be administered intra-arterial iodinated contrast. Reevaluate eGFR 48 hours after the imaging procedure; restart metformin if renal function is stable. Iodinated contrast agents appear to increase the risk of metformin-induced lactic acidosis, possibly as a result of worsening renal function.
Darunavir; Cobicistat; Emtricitabine; Tenofovir alafenamide: (Moderate) Monitor for changes in renal function if tenofovir alafenamide is administered in combination with nephrotoxic agents, such as radiopaque contrast agents. Tenofovir is primarily excreted via the kidneys by a combination of glomerular filtration and active tubular secretion. Coadministration of tenofovir alafenamide with a drug that reduces renal function or competes for active tubular secretion may increase concentrations of tenofovir and other renally eliminated drugs; thus, increasing the risk of developing renal-related adverse reactions.
Deferasirox: (Moderate) Acute renal failure has been reported during treatment with deferasirox. Coadministration of deferasirox with other potentially nephrotoxic drugs, including radiopaque contrast agents, may increase the risk of this toxicity. Monitor serum creatinine and/or creatinine clearance in patients who are receiving deferasirox and nephrotoxic drugs concomitantly.
Desipramine: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering the use of intrathecal radiopaque contrast agents. Tricyclic antidepressants should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Dexamethasone: (Major) Serious adverse events, including death, have been observed during intrathecal administration of both corticosteroids (i.e., dexamethasone) and radiopaque contrast agents (i.e., iohexol); therefore, concurrent use of these medications via the intrathecal route is contraindicated. Cases of cortical blindness, stroke, spinal cord infarction, paralysis, seizures, nerve injury, brain edema, and death have been temporally associated (i.e., within minutes to 48 hours after injection) with epidural administration of injectable corticosteroids. In addition, patients inadvertently administered iohexol formulations not indicated for intrathecal use have experienced seizures, convulsions, cerebral hemorrhages, brain edema, and death. Administering these medications together via the intrathecal route may increase the risk for serious adverse events.
Dexmethylphenidate: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering the use of intrathecal radiopaque contrast agents. Methylphenidate derivatives should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Dextroamphetamine: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering the use of intrathecal radiopaque contrast agents. Amphetamines should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Dextromethorphan; Bupropion: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering intrathecal radiopaque contrast agents. Bupropion should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Dextromethorphan; Diphenhydramine; Phenylephrine: (Major) Do not administer non-ionic contrast media intra-arterially after the administration of vasopressors since they strongly potentiate neurologic effects.
Dextromethorphan; Guaifenesin; Phenylephrine: (Major) Do not administer non-ionic contrast media intra-arterially after the administration of vasopressors since they strongly potentiate neurologic effects.
Diclofenac: (Moderate) Nonsteroidal anti-inflammatory drugs (NSAIDs) may increase the risk for nephrotoxicity when given to patients receiving a contrast agents. When possible, withhold NSAID therapy during administration of a contrast agent.
Diclofenac; Misoprostol: (Moderate) Nonsteroidal anti-inflammatory drugs (NSAIDs) may increase the risk for nephrotoxicity when given to patients receiving a contrast agents. When possible, withhold NSAID therapy during administration of a contrast agent.
Diethylpropion: (Major) Use of medications that lower the seizure threshold, such as diethylpropion, should be carefully evaluated when considering non-ionic contrast media. Such medications should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Diflunisal: (Moderate) Nonsteroidal anti-inflammatory drugs (NSAIDs) may increase the risk for nephrotoxicity when given to patients receiving a contrast agents. When possible, withhold NSAID therapy during administration of a contrast agent.
Diphenhydramine; Ibuprofen: (Moderate) Nonsteroidal anti-inflammatory drugs (NSAIDs) may increase the risk for nephrotoxicity when given to patients receiving a contrast agents. When possible, withhold NSAID therapy during administration of a contrast agent.
Diphenhydramine; Naproxen: (Moderate) Nonsteroidal anti-inflammatory drugs (NSAIDs) may increase the risk for nephrotoxicity when given to patients receiving a contrast agents. When possible, withhold NSAID therapy during administration of a contrast agent.
Diphenhydramine; Phenylephrine: (Major) Do not administer non-ionic contrast media intra-arterially after the administration of vasopressors since they strongly potentiate neurologic effects.
Dopamine: (Major) Do not administer non-ionic contrast media intra-arterially after the administration of vasopressors since they strongly potentiate neurologic effects.
Doravirine; Lamivudine; Tenofovir disoproxil fumarate: (Moderate) Tenofovir-containing products should be avoided with concurrent or recent use of a nephrotoxic agent, such as radiopaque contrast agents. Tenofovir is primarily excreted via the kidneys by a combination of glomerular filtration and active tubular secretion. Coadministration of tenofovir with drugs that are eliminated by active tubular secretion may increase concentrations of tenofovir and/or the co-administered drug. Drugs that decrease renal function may also increase concentrations of tenofovir. Renal impairment, which may include hypophosphatemia, has been reported with the use of tenofovir with a majority of the cases occurring in patients who have underlying systemic or renal disease or who are concurrently taking nephrotoxic agents. Monitor patients receiving concomitant nephrotoxic agents for changes in serum creatinine and phosphorus.
Dorzolamide; Timolol: (Moderate) Use caution when administering non-ionic contrast media to patients taking beta-blockers. Beta-blockers lower the threshold for and increase the severity of contrast reactions and reduce the responsiveness of treatment of hypersensitivity reactions with epinephrine.
Doxepin: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering the use of intrathecal radiopaque contrast agents. Tricyclic antidepressants should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Droxidopa: (Major) Do not administer non-ionic contrast media intra-arterially after the administration of vasopressors since they strongly potentiate neurologic effects.
Efavirenz; Emtricitabine; Tenofovir Disoproxil Fumarate: (Moderate) Tenofovir-containing products should be avoided with concurrent or recent use of a nephrotoxic agent, such as radiopaque contrast agents. Tenofovir is primarily excreted via the kidneys by a combination of glomerular filtration and active tubular secretion. Coadministration of tenofovir with drugs that are eliminated by active tubular secretion may increase concentrations of tenofovir and/or the co-administered drug. Drugs that decrease renal function may also increase concentrations of tenofovir. Renal impairment, which may include hypophosphatemia, has been reported with the use of tenofovir with a majority of the cases occurring in patients who have underlying systemic or renal disease or who are concurrently taking nephrotoxic agents. Monitor patients receiving concomitant nephrotoxic agents for changes in serum creatinine and phosphorus.
Efavirenz; Lamivudine; Tenofovir Disoproxil Fumarate: (Moderate) Tenofovir-containing products should be avoided with concurrent or recent use of a nephrotoxic agent, such as radiopaque contrast agents. Tenofovir is primarily excreted via the kidneys by a combination of glomerular filtration and active tubular secretion. Coadministration of tenofovir with drugs that are eliminated by active tubular secretion may increase concentrations of tenofovir and/or the co-administered drug. Drugs that decrease renal function may also increase concentrations of tenofovir. Renal impairment, which may include hypophosphatemia, has been reported with the use of tenofovir with a majority of the cases occurring in patients who have underlying systemic or renal disease or who are concurrently taking nephrotoxic agents. Monitor patients receiving concomitant nephrotoxic agents for changes in serum creatinine and phosphorus.
Elvitegravir; Cobicistat; Emtricitabine; Tenofovir Alafenamide: (Moderate) Monitor for changes in renal function if tenofovir alafenamide is administered in combination with nephrotoxic agents, such as radiopaque contrast agents. Tenofovir is primarily excreted via the kidneys by a combination of glomerular filtration and active tubular secretion. Coadministration of tenofovir alafenamide with a drug that reduces renal function or competes for active tubular secretion may increase concentrations of tenofovir and other renally eliminated drugs; thus, increasing the risk of developing renal-related adverse reactions.
Elvitegravir; Cobicistat; Emtricitabine; Tenofovir Disoproxil Fumarate: (Moderate) Tenofovir-containing products should be avoided with concurrent or recent use of a nephrotoxic agent, such as radiopaque contrast agents. Tenofovir is primarily excreted via the kidneys by a combination of glomerular filtration and active tubular secretion. Coadministration of tenofovir with drugs that are eliminated by active tubular secretion may increase concentrations of tenofovir and/or the co-administered drug. Drugs that decrease renal function may also increase concentrations of tenofovir. Renal impairment, which may include hypophosphatemia, has been reported with the use of tenofovir with a majority of the cases occurring in patients who have underlying systemic or renal disease or who are concurrently taking nephrotoxic agents. Monitor patients receiving concomitant nephrotoxic agents for changes in serum creatinine and phosphorus.
Empagliflozin; Linagliptin; Metformin: (Major) Discontinue metformin at the time of, or before, administration of non-ionic contrast media to patients with an eGFR of 30 to 60 mL/minute/1.73 m2, history of liver disease, alcoholism, or heart failure, or who will be administered intra-arterial iodinated contrast. Reevaluate eGFR 48 hours after the imaging procedure; restart metformin if renal function is stable. Iodinated contrast agents appear to increase the risk of metformin-induced lactic acidosis, possibly as a result of worsening renal function.
Empagliflozin; Metformin: (Major) Discontinue metformin at the time of, or before, administration of non-ionic contrast media to patients with an eGFR of 30 to 60 mL/minute/1.73 m2, history of liver disease, alcoholism, or heart failure, or who will be administered intra-arterial iodinated contrast. Reevaluate eGFR 48 hours after the imaging procedure; restart metformin if renal function is stable. Iodinated contrast agents appear to increase the risk of metformin-induced lactic acidosis, possibly as a result of worsening renal function.
Emtricitabine; Rilpivirine; Tenofovir alafenamide: (Moderate) Monitor for changes in renal function if tenofovir alafenamide is administered in combination with nephrotoxic agents, such as radiopaque contrast agents. Tenofovir is primarily excreted via the kidneys by a combination of glomerular filtration and active tubular secretion. Coadministration of tenofovir alafenamide with a drug that reduces renal function or competes for active tubular secretion may increase concentrations of tenofovir and other renally eliminated drugs; thus, increasing the risk of developing renal-related adverse reactions.
Emtricitabine; Rilpivirine; Tenofovir Disoproxil Fumarate: (Moderate) Tenofovir-containing products should be avoided with concurrent or recent use of a nephrotoxic agent, such as radiopaque contrast agents. Tenofovir is primarily excreted via the kidneys by a combination of glomerular filtration and active tubular secretion. Coadministration of tenofovir with drugs that are eliminated by active tubular secretion may increase concentrations of tenofovir and/or the co-administered drug. Drugs that decrease renal function may also increase concentrations of tenofovir. Renal impairment, which may include hypophosphatemia, has been reported with the use of tenofovir with a majority of the cases occurring in patients who have underlying systemic or renal disease or who are concurrently taking nephrotoxic agents. Monitor patients receiving concomitant nephrotoxic agents for changes in serum creatinine and phosphorus.
Emtricitabine; Tenofovir alafenamide: (Moderate) Monitor for changes in renal function if tenofovir alafenamide is administered in combination with nephrotoxic agents, such as radiopaque contrast agents. Tenofovir is primarily excreted via the kidneys by a combination of glomerular filtration and active tubular secretion. Coadministration of tenofovir alafenamide with a drug that reduces renal function or competes for active tubular secretion may increase concentrations of tenofovir and other renally eliminated drugs; thus, increasing the risk of developing renal-related adverse reactions.
Emtricitabine; Tenofovir Disoproxil Fumarate: (Moderate) Tenofovir-containing products should be avoided with concurrent or recent use of a nephrotoxic agent, such as radiopaque contrast agents. Tenofovir is primarily excreted via the kidneys by a combination of glomerular filtration and active tubular secretion. Coadministration of tenofovir with drugs that are eliminated by active tubular secretion may increase concentrations of tenofovir and/or the co-administered drug. Drugs that decrease renal function may also increase concentrations of tenofovir. Renal impairment, which may include hypophosphatemia, has been reported with the use of tenofovir with a majority of the cases occurring in patients who have underlying systemic or renal disease or who are concurrently taking nephrotoxic agents. Monitor patients receiving concomitant nephrotoxic agents for changes in serum creatinine and phosphorus.
Enalapril, Enalaprilat: (Moderate) Because the use of other nephrotoxic drugs, including ACE inhibitors, is an additive risk factor for nephrotoxicity in patients receiving radiopaque contrast agents, ACE inhibitor therapy should be withheld, when possible, during radiopaque contrast agent administration.
Enalapril; Hydrochlorothiazide, HCTZ: (Major) Do not use diuretics before non-ionic contrast media administration. Concomitant use of diuretics and non-ionic contrast media may increase the risk for acute kidney injury, including renal failure. (Moderate) Because the use of other nephrotoxic drugs, including ACE inhibitors, is an additive risk factor for nephrotoxicity in patients receiving radiopaque contrast agents, ACE inhibitor therapy should be withheld, when possible, during radiopaque contrast agent administration.
Entecavir: (Moderate) Because entecavir is primarily eliminated by the kidneys and radiopaque contrast agents can affect renal function, concurrent administration with radiopaque contrast agents may increase the serum concentrations of entecavir and adverse events. The manufacturer of entecavir recommends monitoring for adverse effects when these drugs are coadministered.
Ephedrine: (Major) Do not administer non-ionic contrast media intra-arterially after the administration of vasopressors since they strongly potentiate neurologic effects.
Ephedrine; Guaifenesin: (Major) Do not administer non-ionic contrast media intra-arterially after the administration of vasopressors since they strongly potentiate neurologic effects.
Epinephrine: (Major) Do not administer non-ionic contrast media intra-arterially after the administration of vasopressors since they strongly potentiate neurologic effects.
Eprosartan; Hydrochlorothiazide, HCTZ: (Major) Do not use diuretics before non-ionic contrast media administration. Concomitant use of diuretics and non-ionic contrast media may increase the risk for acute kidney injury, including renal failure.
Ergotamine; Caffeine: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering intrathecal radiopaque contrast agents. Caffeine and caffeine containing products should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours post-procedure.
Ertugliflozin; Metformin: (Major) Discontinue metformin at the time of, or before, administration of non-ionic contrast media to patients with an eGFR of 30 to 60 mL/minute/1.73 m2, history of liver disease, alcoholism, or heart failure, or who will be administered intra-arterial iodinated contrast. Reevaluate eGFR 48 hours after the imaging procedure; restart metformin if renal function is stable. Iodinated contrast agents appear to increase the risk of metformin-induced lactic acidosis, possibly as a result of worsening renal function.
Esmolol: (Moderate) Use caution when administering non-ionic contrast media to patients taking beta-blockers. Beta-blockers lower the threshold for and increase the severity of contrast reactions and reduce the responsiveness of treatment of hypersensitivity reactions with epinephrine.
Ethacrynic Acid: (Major) Do not use diuretics before non-ionic contrast media administration. Concomitant use of diuretics and non-ionic contrast media may increase the risk for acute kidney injury, including renal failure.
Etodolac: (Moderate) Nonsteroidal anti-inflammatory drugs (NSAIDs) may increase the risk for nephrotoxicity when given to patients receiving a contrast agents. When possible, withhold NSAID therapy during administration of a contrast agent.
Fenoprofen: (Moderate) Nonsteroidal anti-inflammatory drugs (NSAIDs) may increase the risk for nephrotoxicity when given to patients receiving a contrast agents. When possible, withhold NSAID therapy during administration of a contrast agent.
Fluphenazine: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering the use of intrathecal radiopaque contrast agents. Phenothiazines should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Flurbiprofen: (Moderate) Nonsteroidal anti-inflammatory drugs (NSAIDs) may increase the risk for nephrotoxicity when given to patients receiving a contrast agents. When possible, withhold NSAID therapy during administration of a contrast agent.
Fosinopril: (Moderate) Because the use of other nephrotoxic drugs, including ACE inhibitors, is an additive risk factor for nephrotoxicity in patients receiving radiopaque contrast agents, ACE inhibitor therapy should be withheld, when possible, during radiopaque contrast agent administration.
Fosinopril; Hydrochlorothiazide, HCTZ: (Major) Do not use diuretics before non-ionic contrast media administration. Concomitant use of diuretics and non-ionic contrast media may increase the risk for acute kidney injury, including renal failure. (Moderate) Because the use of other nephrotoxic drugs, including ACE inhibitors, is an additive risk factor for nephrotoxicity in patients receiving radiopaque contrast agents, ACE inhibitor therapy should be withheld, when possible, during radiopaque contrast agent administration.
Furosemide: (Major) Do not use diuretics before non-ionic contrast media administration. Concomitant use of diuretics and non-ionic contrast media may increase the risk for acute kidney injury, including renal failure.
Gentamicin: (Moderate) Because the use of other nephrotoxic drugs, such as aminoglycoside antibiotics, is an additive risk factor for nephrotoxicity in patients receiving radiopaque contrast agents, concomitant use should be avoided when possible.
Glipizide; Metformin: (Major) Discontinue metformin at the time of, or before, administration of non-ionic contrast media to patients with an eGFR of 30 to 60 mL/minute/1.73 m2, history of liver disease, alcoholism, or heart failure, or who will be administered intra-arterial iodinated contrast. Reevaluate eGFR 48 hours after the imaging procedure; restart metformin if renal function is stable. Iodinated contrast agents appear to increase the risk of metformin-induced lactic acidosis, possibly as a result of worsening renal function.
Glyburide; Metformin: (Major) Discontinue metformin at the time of, or before, administration of non-ionic contrast media to patients with an eGFR of 30 to 60 mL/minute/1.73 m2, history of liver disease, alcoholism, or heart failure, or who will be administered intra-arterial iodinated contrast. Reevaluate eGFR 48 hours after the imaging procedure; restart metformin if renal function is stable. Iodinated contrast agents appear to increase the risk of metformin-induced lactic acidosis, possibly as a result of worsening renal function.
Green Tea: (Major) Some, but not all, green tea products contain caffeine. Use of medications that lower the seizure threshold should be carefully evaluated when considering intrathecal radiopaque contrast agents. Caffeine and caffeine containing products including green tea should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Guaifenesin; Phenylephrine: (Major) Do not administer non-ionic contrast media intra-arterially after the administration of vasopressors since they strongly potentiate neurologic effects.
Haloperidol: (Major) Haloperidol lowers the seizure threshold and should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Hydrochlorothiazide, HCTZ: (Major) Do not use diuretics before non-ionic contrast media administration. Concomitant use of diuretics and non-ionic contrast media may increase the risk for acute kidney injury, including renal failure.
Hydrochlorothiazide, HCTZ; Moexipril: (Major) Do not use diuretics before non-ionic contrast media administration. Concomitant use of diuretics and non-ionic contrast media may increase the risk for acute kidney injury, including renal failure. (Moderate) Because the use of other nephrotoxic drugs, including ACE inhibitors, is an additive risk factor for nephrotoxicity in patients receiving radiopaque contrast agents, ACE inhibitor therapy should be withheld, when possible, during radiopaque contrast agent administration.
Hydrocodone; Ibuprofen: (Moderate) Nonsteroidal anti-inflammatory drugs (NSAIDs) may increase the risk for nephrotoxicity when given to patients receiving a contrast agents. When possible, withhold NSAID therapy during administration of a contrast agent.
Hydrocortisone: (Major) Serious adverse events, including death, have been observed during intrathecal administration of both corticosteroids (i.e., hydrocortisone) and radiopaque contrast agents (i.e., iohexol); therefore, concurrent use of these medications via the intrathecal route is contraindicated. Cases of cortical blindness, stroke, spinal cord infarction, paralysis, seizures, nerve injury, brain edema, and death have been temporally associated (i.e., within minutes to 48 hours after injection) with epidural administration of injectable corticosteroids. In addition, patients inadvertently administered iohexol formulations not indicated for intrathecal use have experienced seizures, convulsions, cerebral hemorrhages, brain edema, and death. Administering these medications together via the intrathecal route may increase the risk for serious adverse events.
Ibandronate: (Moderate) Theoretically, coadministration of intravenous ibandronate with other potentially nephrotoxic drugs, such as radiopaque contrast agents, may increase the risk of developing nephrotoxicity.
Ibuprofen: (Moderate) Nonsteroidal anti-inflammatory drugs (NSAIDs) may increase the risk for nephrotoxicity when given to patients receiving a contrast agents. When possible, withhold NSAID therapy during administration of a contrast agent.
Ibuprofen; Famotidine: (Moderate) Nonsteroidal anti-inflammatory drugs (NSAIDs) may increase the risk for nephrotoxicity when given to patients receiving a contrast agents. When possible, withhold NSAID therapy during administration of a contrast agent.
Ibuprofen; Oxycodone: (Moderate) Nonsteroidal anti-inflammatory drugs (NSAIDs) may increase the risk for nephrotoxicity when given to patients receiving a contrast agents. When possible, withhold NSAID therapy during administration of a contrast agent.
Ibuprofen; Pseudoephedrine: (Moderate) Nonsteroidal anti-inflammatory drugs (NSAIDs) may increase the risk for nephrotoxicity when given to patients receiving a contrast agents. When possible, withhold NSAID therapy during administration of a contrast agent.
Iloperidone: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering intrathecal radiopaque contrast agents. Antipsychotics should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours post-procedure. Iloperidone has not been associated with seizure activity more frequently than placebo in clinical trials; however, lowering of the seizure threshold is generally a class effect among antipsychotics and caution is advised.
Imipramine: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering the use of intrathecal radiopaque contrast agents. Tricyclic antidepressants should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Indomethacin: (Moderate) Nonsteroidal anti-inflammatory drugs (NSAIDs) may increase the risk for nephrotoxicity when given to patients receiving a contrast agents. When possible, withhold NSAID therapy during administration of a contrast agent.
Irbesartan; Hydrochlorothiazide, HCTZ: (Major) Do not use diuretics before non-ionic contrast media administration. Concomitant use of diuretics and non-ionic contrast media may increase the risk for acute kidney injury, including renal failure.
Isocarboxazid: (Major) Discontinue monoamine oxidase inhibitors (MAOIs) at least 48 hours before myelography with iohexol and do not resume for at least 24 hours post procedure due to increased seizure risk. In non-elective procedures in patients on these drugs, consider prophylactic use of anticonvulsants.
Ketoprofen: (Moderate) Nonsteroidal anti-inflammatory drugs (NSAIDs) may increase the risk for nephrotoxicity when given to patients receiving a contrast agents. When possible, withhold NSAID therapy during administration of a contrast agent.
Ketorolac: (Moderate) Nonsteroidal anti-inflammatory drugs (NSAIDs) may increase the risk for nephrotoxicity when given to patients receiving a contrast agents. When possible, withhold NSAID therapy during administration of a contrast agent.
Labetalol: (Moderate) Use caution when administering non-ionic contrast media to patients taking beta-blockers. Beta-blockers lower the threshold for and increase the severity of contrast reactions and reduce the responsiveness of treatment of hypersensitivity reactions with epinephrine.
Lamivudine; Tenofovir Disoproxil Fumarate: (Moderate) Tenofovir-containing products should be avoided with concurrent or recent use of a nephrotoxic agent, such as radiopaque contrast agents. Tenofovir is primarily excreted via the kidneys by a combination of glomerular filtration and active tubular secretion. Coadministration of tenofovir with drugs that are eliminated by active tubular secretion may increase concentrations of tenofovir and/or the co-administered drug. Drugs that decrease renal function may also increase concentrations of tenofovir. Renal impairment, which may include hypophosphatemia, has been reported with the use of tenofovir with a majority of the cases occurring in patients who have underlying systemic or renal disease or who are concurrently taking nephrotoxic agents. Monitor patients receiving concomitant nephrotoxic agents for changes in serum creatinine and phosphorus.
Levobunolol: (Moderate) Use caution when administering non-ionic contrast media to patients taking beta-blockers. Beta-blockers lower the threshold for and increase the severity of contrast reactions and reduce the responsiveness of treatment of hypersensitivity reactions with epinephrine.
Lidocaine; Epinephrine: (Major) Do not administer non-ionic contrast media intra-arterially after the administration of vasopressors since they strongly potentiate neurologic effects.
Linagliptin; Metformin: (Major) Discontinue metformin at the time of, or before, administration of non-ionic contrast media to patients with an eGFR of 30 to 60 mL/minute/1.73 m2, history of liver disease, alcoholism, or heart failure, or who will be administered intra-arterial iodinated contrast. Reevaluate eGFR 48 hours after the imaging procedure; restart metformin if renal function is stable. Iodinated contrast agents appear to increase the risk of metformin-induced lactic acidosis, possibly as a result of worsening renal function.
Linezolid: (Major) Discontinue linezolid at least 48 hours before myelography with iohexol and do not resume for at least 24 hours post procedure due to increased seizure risk. In non-elective procedures in patients on these drugs, consider prophylactic use of anticonvulsants.
Lisdexamfetamine: (Major) Use of medications that lower the seizure threshold, such as lisdexamfetamine, should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Lisinopril: (Moderate) Because the use of other nephrotoxic drugs, including ACE inhibitors, is an additive risk factor for nephrotoxicity in patients receiving radiopaque contrast agents, ACE inhibitor therapy should be withheld, when possible, during radiopaque contrast agent administration.
Lisinopril; Hydrochlorothiazide, HCTZ: (Major) Do not use diuretics before non-ionic contrast media administration. Concomitant use of diuretics and non-ionic contrast media may increase the risk for acute kidney injury, including renal failure. (Moderate) Because the use of other nephrotoxic drugs, including ACE inhibitors, is an additive risk factor for nephrotoxicity in patients receiving radiopaque contrast agents, ACE inhibitor therapy should be withheld, when possible, during radiopaque contrast agent administration.
Loop diuretics: (Major) Do not use diuretics before non-ionic contrast media administration. Concomitant use of diuretics and non-ionic contrast media may increase the risk for acute kidney injury, including renal failure.
Lorazepam: (Moderate) The use of intrathecal radiopaque contrast agents is associated with a risk of seizures. Patients should be instructed to continue using benzodiazepines during procedures or exams that require the use of intrathecal radiopaque contrast agents as abrupt discontinuation of benzodiazepines may also increase seizure risk.
Losartan; Hydrochlorothiazide, HCTZ: (Major) Do not use diuretics before non-ionic contrast media administration. Concomitant use of diuretics and non-ionic contrast media may increase the risk for acute kidney injury, including renal failure.
Loxapine: (Major) Loxapine lower the seizure threshold and should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Lurasidone: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering intrathecal radiopaque contrast agents. Antipsychotics should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours post-procedure.
Maprotiline: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering the use of intrathecal radiopaque contrast agents. Maprotiline should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Meclofenamate Sodium: (Moderate) Nonsteroidal anti-inflammatory drugs (NSAIDs) may increase the risk for nephrotoxicity when given to patients receiving a contrast agents. When possible, withhold NSAID therapy during administration of a contrast agent.
Mefenamic Acid: (Moderate) Nonsteroidal anti-inflammatory drugs (NSAIDs) may increase the risk for nephrotoxicity when given to patients receiving a contrast agents. When possible, withhold NSAID therapy during administration of a contrast agent.
Meloxicam: (Moderate) Nonsteroidal anti-inflammatory drugs (NSAIDs) may increase the risk for nephrotoxicity when given to patients receiving a contrast agents. When possible, withhold NSAID therapy during administration of a contrast agent.
Metformin: (Major) Discontinue metformin at the time of, or before, administration of non-ionic contrast media to patients with an eGFR of 30 to 60 mL/minute/1.73 m2, history of liver disease, alcoholism, or heart failure, or who will be administered intra-arterial iodinated contrast. Reevaluate eGFR 48 hours after the imaging procedure; restart metformin if renal function is stable. Iodinated contrast agents appear to increase the risk of metformin-induced lactic acidosis, possibly as a result of worsening renal function.
Metformin; Repaglinide: (Major) Discontinue metformin at the time of, or before, administration of non-ionic contrast media to patients with an eGFR of 30 to 60 mL/minute/1.73 m2, history of liver disease, alcoholism, or heart failure, or who will be administered intra-arterial iodinated contrast. Reevaluate eGFR 48 hours after the imaging procedure; restart metformin if renal function is stable. Iodinated contrast agents appear to increase the risk of metformin-induced lactic acidosis, possibly as a result of worsening renal function.
Metformin; Saxagliptin: (Major) Discontinue metformin at the time of, or before, administration of non-ionic contrast media to patients with an eGFR of 30 to 60 mL/minute/1.73 m2, history of liver disease, alcoholism, or heart failure, or who will be administered intra-arterial iodinated contrast. Reevaluate eGFR 48 hours after the imaging procedure; restart metformin if renal function is stable. Iodinated contrast agents appear to increase the risk of metformin-induced lactic acidosis, possibly as a result of worsening renal function.
Metformin; Sitagliptin: (Major) Discontinue metformin at the time of, or before, administration of non-ionic contrast media to patients with an eGFR of 30 to 60 mL/minute/1.73 m2, history of liver disease, alcoholism, or heart failure, or who will be administered intra-arterial iodinated contrast. Reevaluate eGFR 48 hours after the imaging procedure; restart metformin if renal function is stable. Iodinated contrast agents appear to increase the risk of metformin-induced lactic acidosis, possibly as a result of worsening renal function.
Methamphetamine: (Major) Methamphetamine lowers the seizure threshold and should be discontinued at least 48 hours before and for at least 24 hours after intrathecal use of contrast media.
Methylphenidate Derivatives: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering the use of intrathecal radiopaque contrast agents. Methylphenidate derivatives should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Methylphenidate: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering the use of intrathecal radiopaque contrast agents. Methylphenidate derivatives should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Methylprednisolone: (Major) Serious adverse events, including death, have been observed during intrathecal administration of both corticosteroids (i.e., methylprednisolone) and radiopaque contrast agents (i.e., iohexol); therefore, concurrent use of these medications via the intrathecal route is contraindicated. Cases of cortical blindness, stroke, spinal cord infarction, paralysis, seizures, nerve injury, brain edema, and death have been temporally associated (i.e., within minutes to 48 hours after injection) with epidural administration of injectable corticosteroids. In addition, patients inadvertently administered iohexol formulations not indicated for intrathecal use have experienced seizures, convulsions, cerebral hemorrhages, brain edema, and death. Administering these medications together via the intrathecal route may increase the risk for serious adverse events.
Metolazone: (Major) Do not use diuretics before non-ionic contrast media administration. Concomitant use of diuretics and non-ionic contrast media may increase the risk for acute kidney injury, including renal failure.
Metoprolol: (Moderate) Use caution when administering non-ionic contrast media to patients taking beta-blockers. Beta-blockers lower the threshold for and increase the severity of contrast reactions and reduce the responsiveness of treatment of hypersensitivity reactions with epinephrine.
Metoprolol; Hydrochlorothiazide, HCTZ: (Major) Do not use diuretics before non-ionic contrast media administration. Concomitant use of diuretics and non-ionic contrast media may increase the risk for acute kidney injury, including renal failure. (Moderate) Use caution when administering non-ionic contrast media to patients taking beta-blockers. Beta-blockers lower the threshold for and increase the severity of contrast reactions and reduce the responsiveness of treatment of hypersensitivity reactions with epinephrine.
Midodrine: (Major) Do not administer non-ionic contrast media intra-arterially after the administration of vasopressors since they strongly potentiate neurologic effects.
Moexipril: (Moderate) Because the use of other nephrotoxic drugs, including ACE inhibitors, is an additive risk factor for nephrotoxicity in patients receiving radiopaque contrast agents, ACE inhibitor therapy should be withheld, when possible, during radiopaque contrast agent administration.
Molindone: (Major) Molindone lowers the seizure threshold and should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Monoamine oxidase inhibitors: (Major) Discontinue monoamine oxidase inhibitors (MAOIs) at least 48 hours before myelography with iohexol and do not resume for at least 24 hours post procedure due to increased seizure risk. In non-elective procedures in patients on these drugs, consider prophylactic use of anticonvulsants.
Nabumetone: (Moderate) Nonsteroidal anti-inflammatory drugs (NSAIDs) may increase the risk for nephrotoxicity when given to patients receiving a contrast agents. When possible, withhold NSAID therapy during administration of a contrast agent.
Nadolol: (Moderate) Use caution when administering non-ionic contrast media to patients taking beta-blockers. Beta-blockers lower the threshold for and increase the severity of contrast reactions and reduce the responsiveness of treatment of hypersensitivity reactions with epinephrine.
Naproxen: (Moderate) Nonsteroidal anti-inflammatory drugs (NSAIDs) may increase the risk for nephrotoxicity when given to patients receiving a contrast agents. When possible, withhold NSAID therapy during administration of a contrast agent.
Naproxen; Esomeprazole: (Moderate) Nonsteroidal anti-inflammatory drugs (NSAIDs) may increase the risk for nephrotoxicity when given to patients receiving a contrast agents. When possible, withhold NSAID therapy during administration of a contrast agent.
Naproxen; Pseudoephedrine: (Moderate) Nonsteroidal anti-inflammatory drugs (NSAIDs) may increase the risk for nephrotoxicity when given to patients receiving a contrast agents. When possible, withhold NSAID therapy during administration of a contrast agent.
Nebivolol: (Moderate) Use caution when administering non-ionic contrast media to patients taking beta-blockers. Beta-blockers lower the threshold for and increase the severity of contrast reactions and reduce the responsiveness of treatment of hypersensitivity reactions with epinephrine.
Nebivolol; Valsartan: (Moderate) Use caution when administering non-ionic contrast media to patients taking beta-blockers. Beta-blockers lower the threshold for and increase the severity of contrast reactions and reduce the responsiveness of treatment of hypersensitivity reactions with epinephrine.
Nonsteroidal antiinflammatory drugs: (Moderate) Nonsteroidal anti-inflammatory drugs (NSAIDs) may increase the risk for nephrotoxicity when given to patients receiving a contrast agents. When possible, withhold NSAID therapy during administration of a contrast agent.
Norepinephrine: (Major) Do not administer non-ionic contrast media intra-arterially after the administration of vasopressors since they strongly potentiate neurologic effects.
Nortriptyline: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering the use of intrathecal radiopaque contrast agents. Tricyclic antidepressants should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Olanzapine: (Major) Atypical antipsychotics may lower the seizure threshold and should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Olanzapine; Fluoxetine: (Major) Atypical antipsychotics may lower the seizure threshold and should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Olanzapine; Samidorphan: (Major) Atypical antipsychotics may lower the seizure threshold and should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Olmesartan; Amlodipine; Hydrochlorothiazide, HCTZ: (Major) Do not use diuretics before non-ionic contrast media administration. Concomitant use of diuretics and non-ionic contrast media may increase the risk for acute kidney injury, including renal failure.
Olmesartan; Hydrochlorothiazide, HCTZ: (Major) Do not use diuretics before non-ionic contrast media administration. Concomitant use of diuretics and non-ionic contrast media may increase the risk for acute kidney injury, including renal failure.
Oxaliplatin: (Major) Avoid coadministration of oxaliplatin with non-ionic contrast media due to the risk of increased oxaliplatin-related adverse reactions. Non-ionic contrast media is known to be potentially nephrotoxic; because platinum-containing drugs like oxaliplatin are eliminated primarily through the kidney, oxaliplatin clearance may be decreased by coadministration with nephrotoxic agents.
Oxaprozin: (Moderate) Nonsteroidal anti-inflammatory drugs (NSAIDs) may increase the risk for nephrotoxicity when given to patients receiving a contrast agents. When possible, withhold NSAID therapy during administration of a contrast agent.
Pamidronate: (Moderate) Coadministration of pamidronate with other nephrotoxic drugs may increase the risk of developing nephrotoxicity following pamidronate administration, even in patients who have normal renal function.
Paromomycin: (Moderate) Because the use of other nephrotoxic drugs, such as aminoglycoside antibiotics, is an additive risk factor for nephrotoxicity in patients receiving radiopaque contrast agents, concomitant use should be avoided when possible.
Perindopril: (Moderate) Because the use of other nephrotoxic drugs, including ACE inhibitors, is an additive risk factor for nephrotoxicity in patients receiving radiopaque contrast agents, ACE inhibitor therapy should be withheld, when possible, during radiopaque contrast agent administration.
Perindopril; Amlodipine: (Moderate) Because the use of other nephrotoxic drugs, including ACE inhibitors, is an additive risk factor for nephrotoxicity in patients receiving radiopaque contrast agents, ACE inhibitor therapy should be withheld, when possible, during radiopaque contrast agent administration.
Perphenazine: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering the use of intrathecal radiopaque contrast agents. Phenothiazines should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Perphenazine; Amitriptyline: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering the use of intrathecal radiopaque contrast agents. Phenothiazines should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure. (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering the use of intrathecal radiopaque contrast agents. Tricyclic antidepressants should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Phendimetrazine: (Major) Phendimetrazine lowers the seizure threshold and should be discontinued at least 48 hours before and for at least 24 hours after intrathecal use of contrast media.
Phenelzine: (Major) Discontinue monoamine oxidase inhibitors (MAOIs) at least 48 hours before myelography with iohexol and do not resume for at least 24 hours post procedure due to increased seizure risk. In non-elective procedures in patients on these drugs, consider prophylactic use of anticonvulsants.
Phenothiazines: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering the use of intrathecal radiopaque contrast agents. Phenothiazines should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Phentermine: (Major) Phentermine lowers the seizure threshold and should be discontinued at least 48 hours before and for at least 24 hours after intrathecal use of contrast media.
Phentermine; Topiramate: (Major) Phentermine lowers the seizure threshold and should be discontinued at least 48 hours before and for at least 24 hours after intrathecal use of contrast media.
Phenylephrine: (Major) Do not administer non-ionic contrast media intra-arterially after the administration of vasopressors since they strongly potentiate neurologic effects.
Pimozide: (Major) Pimozide lowers the seizure threshold and should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Pindolol: (Moderate) Use caution when administering non-ionic contrast media to patients taking beta-blockers. Beta-blockers lower the threshold for and increase the severity of contrast reactions and reduce the responsiveness of treatment of hypersensitivity reactions with epinephrine.
Pioglitazone; Metformin: (Major) Discontinue metformin at the time of, or before, administration of non-ionic contrast media to patients with an eGFR of 30 to 60 mL/minute/1.73 m2, history of liver disease, alcoholism, or heart failure, or who will be administered intra-arterial iodinated contrast. Reevaluate eGFR 48 hours after the imaging procedure; restart metformin if renal function is stable. Iodinated contrast agents appear to increase the risk of metformin-induced lactic acidosis, possibly as a result of worsening renal function.
Piroxicam: (Moderate) Nonsteroidal anti-inflammatory drugs (NSAIDs) may increase the risk for nephrotoxicity when given to patients receiving a contrast agents. When possible, withhold NSAID therapy during administration of a contrast agent.
Plazomicin: (Moderate) Because the use of other nephrotoxic drugs, such as aminoglycoside antibiotics, is an additive risk factor for nephrotoxicity in patients receiving radiopaque contrast agents, concomitant use should be avoided when possible.
Potassium-sparing diuretics: (Major) Do not use diuretics before non-ionic contrast media administration. Concomitant use of diuretics and non-ionic contrast media may increase the risk for acute kidney injury, including renal failure.
Prednisolone: (Major) Serious adverse events, including death, have been observed during intrathecal administration of both corticosteroids (i.e., prednisolone) and radiopaque contrast agents (i.e., iohexol); therefore, concurrent use of these medications via the intrathecal route is contraindicated. Cases of cortical blindness, stroke, spinal cord infarction, paralysis, seizures, nerve injury, brain edema, and death have been temporally associated (i.e., within minutes to 48 hours after injection) with epidural administration of injectable corticosteroids. In addition, patients inadvertently administered iohexol formulations not indicated for intrathecal use have experienced seizures, convulsions, cerebral hemorrhages, brain edema, and death. Administering these medications together via the intrathecal route may increase the risk for serious adverse events.
Prilocaine; Epinephrine: (Major) Do not administer non-ionic contrast media intra-arterially after the administration of vasopressors since they strongly potentiate neurologic effects.
Prochlorperazine: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering the use of intrathecal radiopaque contrast agents. Phenothiazines should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Promethazine: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering the use of intrathecal radiopaque contrast agents. Phenothiazines should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Promethazine; Dextromethorphan: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering the use of intrathecal radiopaque contrast agents. Phenothiazines should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Promethazine; Phenylephrine: (Major) Do not administer non-ionic contrast media intra-arterially after the administration of vasopressors since they strongly potentiate neurologic effects. (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering the use of intrathecal radiopaque contrast agents. Phenothiazines should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Propranolol: (Moderate) Use caution when administering non-ionic contrast media to patients taking beta-blockers. Beta-blockers lower the threshold for and increase the severity of contrast reactions and reduce the responsiveness of treatment of hypersensitivity reactions with epinephrine.
Protriptyline: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering the use of intrathecal radiopaque contrast agents. Tricyclic antidepressants should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Quetiapine: (Major) Quetiapine lowers the seizure threshold and should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Quinapril: (Moderate) Because the use of other nephrotoxic drugs, including ACE inhibitors, is an additive risk factor for nephrotoxicity in patients receiving radiopaque contrast agents, ACE inhibitor therapy should be withheld, when possible, during radiopaque contrast agent administration.
Quinapril; Hydrochlorothiazide, HCTZ: (Major) Do not use diuretics before non-ionic contrast media administration. Concomitant use of diuretics and non-ionic contrast media may increase the risk for acute kidney injury, including renal failure. (Moderate) Because the use of other nephrotoxic drugs, including ACE inhibitors, is an additive risk factor for nephrotoxicity in patients receiving radiopaque contrast agents, ACE inhibitor therapy should be withheld, when possible, during radiopaque contrast agent administration.
Ramipril: (Moderate) Because the use of other nephrotoxic drugs, including ACE inhibitors, is an additive risk factor for nephrotoxicity in patients receiving radiopaque contrast agents, ACE inhibitor therapy should be withheld, when possible, during radiopaque contrast agent administration.
Risperidone: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering intrathecal radiopaque contrast agents. Antipsychotics should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Serdexmethylphenidate; Dexmethylphenidate: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering the use of intrathecal radiopaque contrast agents. Methylphenidate derivatives should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Sodium Iodide: (Moderate) Administration of non-ionic contrast media may interfere with thyroid uptake of radioactive sodium iodide (I-131) and decrease therapeutic and diagnostic efficacy in patients with carcinoma of the thyroid. The decrease in efficacy lasts for 6 to 8 weeks.
Sodium Oxybate: (Major) Sodium oxybate lowers seizure threshold and should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Sotalol: (Moderate) Use caution when administering non-ionic contrast media to patients taking beta-blockers. Beta-blockers lower the threshold for and increase the severity of contrast reactions and reduce the responsiveness of treatment of hypersensitivity reactions with epinephrine.
Spironolactone: (Major) Do not use diuretics before non-ionic contrast media administration. Concomitant use of diuretics and non-ionic contrast media may increase the risk for acute kidney injury, including renal failure.
Spironolactone; Hydrochlorothiazide, HCTZ: (Major) Do not use diuretics before non-ionic contrast media administration. Concomitant use of diuretics and non-ionic contrast media may increase the risk for acute kidney injury, including renal failure.
Streptomycin: (Moderate) Because the use of other nephrotoxic drugs, such as aminoglycoside antibiotics, is an additive risk factor for nephrotoxicity in patients receiving radiopaque contrast agents, concomitant use should be avoided when possible.
Sulindac: (Moderate) Nonsteroidal anti-inflammatory drugs (NSAIDs) may increase the risk for nephrotoxicity when given to patients receiving a contrast agents. When possible, withhold NSAID therapy during administration of a contrast agent.
Sumatriptan; Naproxen: (Moderate) Nonsteroidal anti-inflammatory drugs (NSAIDs) may increase the risk for nephrotoxicity when given to patients receiving a contrast agents. When possible, withhold NSAID therapy during administration of a contrast agent.
Telmisartan; Hydrochlorothiazide, HCTZ: (Major) Do not use diuretics before non-ionic contrast media administration. Concomitant use of diuretics and non-ionic contrast media may increase the risk for acute kidney injury, including renal failure.
Tenofovir Alafenamide: (Moderate) Monitor for changes in renal function if tenofovir alafenamide is administered in combination with nephrotoxic agents, such as radiopaque contrast agents. Tenofovir is primarily excreted via the kidneys by a combination of glomerular filtration and active tubular secretion. Coadministration of tenofovir alafenamide with a drug that reduces renal function or competes for active tubular secretion may increase concentrations of tenofovir and other renally eliminated drugs; thus, increasing the risk of developing renal-related adverse reactions.
Tenofovir Alafenamide: (Moderate) Monitor for changes in renal function if tenofovir alafenamide is administered in combination with nephrotoxic agents, such as radiopaque contrast agents. Tenofovir is primarily excreted via the kidneys by a combination of glomerular filtration and active tubular secretion. Coadministration of tenofovir alafenamide with a drug that reduces renal function or competes for active tubular secretion may increase concentrations of tenofovir and other renally eliminated drugs; thus, increasing the risk of developing renal-related adverse reactions.
Tenofovir Disoproxil Fumarate: (Moderate) Tenofovir-containing products should be avoided with concurrent or recent use of a nephrotoxic agent, such as radiopaque contrast agents. Tenofovir is primarily excreted via the kidneys by a combination of glomerular filtration and active tubular secretion. Coadministration of tenofovir with drugs that are eliminated by active tubular secretion may increase concentrations of tenofovir and/or the co-administered drug. Drugs that decrease renal function may also increase concentrations of tenofovir. Renal impairment, which may include hypophosphatemia, has been reported with the use of tenofovir with a majority of the cases occurring in patients who have underlying systemic or renal disease or who are concurrently taking nephrotoxic agents. Monitor patients receiving concomitant nephrotoxic agents for changes in serum creatinine and phosphorus.
Thiazide diuretics: (Major) Do not use diuretics before non-ionic contrast media administration. Concomitant use of diuretics and non-ionic contrast media may increase the risk for acute kidney injury, including renal failure.
Thioridazine: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering the use of intrathecal radiopaque contrast agents. Phenothiazines should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Thiothixene: (Major) Use of medications that lower the seizure threshold, such as thiothixene, should be carefully evaluated when considering intrathecal radiopaque contrast agents. Antipsychotics should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Timolol: (Moderate) Use caution when administering non-ionic contrast media to patients taking beta-blockers. Beta-blockers lower the threshold for and increase the severity of contrast reactions and reduce the responsiveness of treatment of hypersensitivity reactions with epinephrine.
Tobramycin: (Moderate) Because the use of other nephrotoxic drugs, such as aminoglycoside antibiotics, is an additive risk factor for nephrotoxicity in patients receiving radiopaque contrast agents, concomitant use should be avoided when possible.
Tolmetin: (Moderate) Nonsteroidal anti-inflammatory drugs (NSAIDs) may increase the risk for nephrotoxicity when given to patients receiving a contrast agents. When possible, withhold NSAID therapy during administration of a contrast agent.
Torsemide: (Major) Do not use diuretics before non-ionic contrast media administration. Concomitant use of diuretics and non-ionic contrast media may increase the risk for acute kidney injury, including renal failure.
Tramadol: (Major) Tramadol lowers the seizure threshold and should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Tramadol; Acetaminophen: (Major) Tramadol lowers the seizure threshold and should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Trandolapril: (Moderate) Because the use of other nephrotoxic drugs, including ACE inhibitors, is an additive risk factor for nephrotoxicity in patients receiving radiopaque contrast agents, ACE inhibitor therapy should be withheld, when possible, during radiopaque contrast agent administration.
Trandolapril; Verapamil: (Moderate) Because the use of other nephrotoxic drugs, including ACE inhibitors, is an additive risk factor for nephrotoxicity in patients receiving radiopaque contrast agents, ACE inhibitor therapy should be withheld, when possible, during radiopaque contrast agent administration.
Tranylcypromine: (Major) Discontinue monoamine oxidase inhibitors (MAOIs) at least 48 hours before myelography with iohexol and do not resume for at least 24 hours post procedure due to increased seizure risk. In non-elective procedures in patients on these drugs, consider prophylactic use of anticonvulsants.
Triamcinolone: (Major) Serious adverse events, including death, have been observed during intrathecal administration of both corticosteroids (i.e., triamcinolone) and radiopaque contrast agents (i.e., iohexol); therefore, concurrent use of these medications via the intrathecal route is contraindicated. Cases of cortical blindness, stroke, spinal cord infarction, paralysis, seizures, nerve injury, brain edema, and death have been temporally associated (i.e., within minutes to 48 hours after injection) with epidural administration of injectable corticosteroids. In addition, patients inadvertently administered iohexol formulations not indicated for intrathecal use have experienced seizures, convulsions, cerebral hemorrhages, brain edema, and death. Administering these medications together via the intrathecal route may increase the risk for serious adverse events.
Triamterene: (Major) Do not use diuretics before non-ionic contrast media administration. Concomitant use of diuretics and non-ionic contrast media may increase the risk for acute kidney injury, including renal failure.
Triamterene; Hydrochlorothiazide, HCTZ: (Major) Do not use diuretics before non-ionic contrast media administration. Concomitant use of diuretics and non-ionic contrast media may increase the risk for acute kidney injury, including renal failure.
Tricyclic antidepressants: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering the use of intrathecal radiopaque contrast agents. Tricyclic antidepressants should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Trifluoperazine: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering the use of intrathecal radiopaque contrast agents. Phenothiazines should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Trimipramine: (Major) Use of medications that lower the seizure threshold should be carefully evaluated when considering the use of intrathecal radiopaque contrast agents. Tricyclic antidepressants should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Valacyclovir: (Moderate) Concomitant use of valacyclovir and contrast agents should be avoided when possible, as use of these drugs together may increase the risk for nephrotoxicity.
Valsartan; Hydrochlorothiazide, HCTZ: (Major) Do not use diuretics before non-ionic contrast media administration. Concomitant use of diuretics and non-ionic contrast media may increase the risk for acute kidney injury, including renal failure.
Vasopressin, ADH: (Major) Do not administer non-ionic contrast media intra-arterially after the administration of vasopressors since they strongly potentiate neurologic effects.
Vasopressors: (Major) Do not administer non-ionic contrast media intra-arterially after the administration of vasopressors since they strongly potentiate neurologic effects.
Voclosporin: (Moderate) Concomitant use of voclosporin and non-ionic contrast media may result in additive nephrotoxicity. Monitor for renal toxicity if concomitant use is required.
Ziprasidone: (Major) Use of medications that lower the seizure threshold, such as ziprasidone, should be carefully evaluated when considering intrathecal radiopaque contrast agents. Antipsychotics should be discontinued at least 48 hours before myelography and should not be resumed for at least 24 hours postprocedure.
Zoledronic Acid: (Moderate) Theoretically, the chronic coadministration of zoledronic acid with other nephrotoxic drugs, such as radiopaque contrast agents, may increase the risk of developing nephrotoxicity, even in patients who have normal renal function.
Iohexol is an iodinated contrast media used to visualize the anatomical structures of the body including blood vessels, tissues, organs, and body cavities. Iodine is the radiopaque component of iohexol, allowing for opacification of vessels in the path of the blood flow of contrast media during angiography and urography. After iohexol injection, internal structures of the human body can be visualized until significant hemodilution occurs. Iohexol can be injected directly into body cavities and provide density sufficient for enhanced radiographic visualization.
Iohexol enhances computed tomographic (CT) imaging through augmentation of radiographic efficiency. The degree of enhancement is directly related to the iodine content in the administered dose; peak iodine blood levels usually occur immediately and dramatically decrease within 5-10 minutes. During CT brain imaging, a lag between contrast media administration and maximum contrast enhancement of up to one hour occurs most likely because the accumulation of iodine within the lesion and the outside blood pool is necessary for visualization; the mechanism by which this occurs is not clear. Because contrast media does not cross the blood-brain barrier, contrast media does not accumulate in normal brain tissue; contrast enhancement of normal brain tissue is most likely secondary to iohexol accumulation within the blood pool. If the presence of a malignant tumor causes a break in the blood-brain barrier, contrast media does accumulate within the interstitial tissues of the tumor; however, adjacent normal brain tissue does not contain contrast medium. During computed tomographic (CT) imaging of the body, enhancement is related to blood flow, concentration of the contrast medium, and extraction of the contrast medium by interstitial tissue of tumors since no barrier exists. In contrast to brain imaging, contrast enhancement during body imaging is due to the relative differences in extravascular diffusion of contrast media between normal and abnormal tissue
Iohexol can be administered orally or can be injected into body cavities or joints. Iohexol can also be administered intravascularly (intravenously or intra-arterially) or intrathecally. Care should be taken to administer only iohexol 180 mg iodine/mL, 240 mg iodine/mL, or 300 mg iodine/mL concentrations intrathecally.
-Route-Specific Pharmacokinetics
Oral Route
Iohexol is not significantly absorbed following oral administration; only 0.1% to 0.5% of an administered dose is excreted by the kidneys. This amount may increase in the presence of bowel perforation or obstruction. Iohexol is well tolerated and readily absorbed if leakage into the peritoneal cavity occurs.
Intravenous Route
After IV administration in 16 adult subjects receiving 500 to 1,500 mg iodine/kg, the Vd of iohexol was 165 mL/kg (range: 108 to 219 mL/kg). The elimination half-life was 12.6 hours, and the clearance was 131 mL/minute (range: 98 to 165 mL/minute); clearance does not appear to be dose dependent. Iohexol does not undergo any significant metabolism, deiodination, or biotransformation, but is primarily eliminated through the kidneys via glomerular filtration. Approximately 90% of the drug is excreted unchanged in the urine within the first 24 hours, with the peak urine concentrations occurring within the first hour after administration.
Other Route(s)
Intravascular administration
Iohexol demonstrates 2-compartment model pharmacokinetics. Following intravascular administration, peak plasma concentrations occur rapidly allowing for quick visualization of the blood, liver, spleen and other organs followed by slow urinary excretion. Iohexol immediately distributes into circulating blood volume and then into the interstitial space; after equilibrium, distribution into the extracellular space occurs. It does not appear that iohexol is significantly deposited into normal tissue. Iohexol is not significantly bound to plasma or serum proteins and does not cross the blood-brain barrier; iohexol probably crosses the placental barrier by simple diffusion. Iohexol does not undergo any significant metabolism, deiodination, or biotransformation but is primarily eliminated through the kidneys via glomerular filtration. The elimination half-life of all iodinated contrast media is approximately 2 hours in patients with normal renal function. Approximately 90% of an intravascular dose is excreted in the urine within the first 24 hours. Maximal opacification of the renal passages may be possible as early as one minute after intravenous injection; urograms become apparent 1 to 3 minutes after injection with optimal contrast occurring in 5 to 15 minutes. In patients with renal impairment, visualization may be delayed or lacking. Maximum contrast enhancement during computed tomography brain imaging can occur up to one hour after injection depending on the type of lesion to be visualized whereas contrast enhancement during computed tomography of the body appears to be greatest soon after bolus administration of the contrast medium. The greatest enhancement for body imaging can be detected by a series of consecutive 2 to 3 second scans (e.g., dynamic computed tomography imaging) performed within 30 to 90 seconds after injection.
Intrathecal administration
Following intrathecal administration, iohexol is rapidly absorbed into the bloodstream from the cerebrospinal fluid (CSF); the mean maximum plasma concentration of iohexol occurs approximately 3.8 hours after intrathecal administration. Once absorbed into the bloodstream, the distribution, metabolism and excretion of iohexol is the same as intravascular administration; 88% of an intrathecal dose is excreted in the urine within the first 24 hours. After intrathecal injection, diagnostic contrast will be provided for up to 30 minutes using conventional radiography; after one hour, contrast of diagnostic quality is usually negligible. However, sufficient contrast for enhanced myelographic computed tomography will be available for several hours post administration. If contrast enhanced CT myelography is to follow conventional myelography, a delay of several hours between procedures should be considered as after administration into the lumbar subarachnoid space, computed tomography shows the presence of contrast medium in the thoracic region in 1 hour, in the cervical region in 2 hours, and the basal cisterns in 3 to 4 hours.
Body cavity/joint administration
When administered into the majority of body cavities or joints, iohexol is rapidly absorbed into the surrounding tissue and the distribution, metabolism and excretion is the same as intravascular administration. When iohexol is used for bladder or uterine examinations, the contrast media is drained from the cavity after completion of the radiographic examination.
-Special Populations
Renal Impairment
In patients with renal impairment, the clearance of all iodinated contrast media, including iohexol, is reduced; the reduction in contrast media clearance correlates to the degree of renal impairment. Depending on the degree of impairment, the half-life of contrast media in patients with renal insufficiency can approach 30 hours. Both hemodialysis and continuous ambulatory peritoneal dialysis are effective in removing contrast media from the body. Approximately 80% to 82% of an administered dose of iohexol is removed after 4 hours of hemodialysis. It is possible that in patients with severely impaired renal function or in infants with immature kidneys, nonrenal excretion such as biliary elimination or hepatic metabolism is increased.