Captopril is an angiotensin-converting enzyme (ACE) inhibitor used in the treatment of hypertension, congestive heart failure, and various renal syndromes such as diabetic nephropathy and scleroderma. Captopril is the first ACE inhibitor to have been marketed in the United States. Captopril has been shown to significantly reduce mortality in patients with heart failure. As the shortest-acting of all ACE inhibitors, it is usually dosed two or three times a day. Captopril contains a sulfhydryl group, which may contribute to its pharmacologic action and account for some adverse reactions that occur at higher doses. Captopril was approved by the FDA in 1981. Its patent expired on February 13, 1996.
General Administration Information
For storage information, see the specific product information within the How Supplied section.
Route-Specific Administration
Oral Administration
-To ensure maximum absorption, administer on an empty stomach 1 hour before meals. Drug absorption is reduced 30-40% by food.
Neutropenia (< 1000/mm3) with myeloid hypoplasia has resulted from use of captopril. About half of the neutropenic patients developed systemic or oral cavity infections or other features of the syndrome of agranulocytosis. Patients with impaired renal function, patients with collagen vascular disease, or patients receiving large daily doses are at greater risk. Neutropenia has usually been detected within 3 months of initiation of captopril; neutrophils generally return to normal within 2 weeks after discontinuation. About 13% of the cases of neutropenia have ended fatally; however, these were usually in patients with serious illness like collagen vascular disease, renal failure, heart failure or immunosuppressant therapy, or a combination of these complicating factors. Evaluate the white blood cell and differential counts prior to initiation of captopril in patients with impaired renal function, and then every 2 weeks for about three months, then periodically. Use captopril only after an assessment of benefit and risk, and then with caution in patients with collagen vascular disease or who are exposed to other drugs known to affect the white cells or immune response, particularly when there is impaired renal function. Instruct patients to report signs of infection (e.g., sore throat, fever) during captopril therapy. Promptly check white cell counts in patients with suspected infection. If neutropenia is confirmed, discontinue captopril and follow patient clinically. Anemia, aplastic anemia, hemolytic anemia, pancytopenia, and thrombocytopenia have also been reported with captopril use.
Captopril can affect renal function. Renal insufficiency, renal failure (unspecified), nephrotic syndrome, polyuria, oliguria, and increased urinary frequency have been reported in 1-2 of 1000 (0.1%-0.2%) patients and are of uncertain relationship to drug use. Transient elevations of BUN or serum creatinine especially in volume or salt depleted patients or those with renovascular hypertension may occur. In addition, rapid reduction of longstanding or markedly elevated blood pressure can result in decreases in the glomerular filtration rate and, in turn, lead to increases in BUN or serum creatinine. Proteinuria occurs at an incidence of approximately 1%. Total urinary proteins > 1 g/day has occurred at an incidence of 0.7%. The majority of these patients has evidence of prior renal disease, were receiving doses of captopril > 150 mg/day, or both. Proteinuria has led to nephrotic syndrome in about 20% of patients. Proteinuria usually subsided within 6 months whether or not captopril was continued. Alterations in BUN and creatinine were rarely reported in the patients with proteinuria.
In approximately 2-4% of adult patients taking captopril, dysgeusia (taste alteration), consisting of diminution or loss of taste perception, can occur but is usually reversible within 2-3 months even if therapy is continued. Dysgeusia may lead to weight loss. Other gastrointestinal reactions reported in 0.5-2% of adult patients receiving captopril, but not at a greater frequency than patients receiving placebo or other therapies in controlled trials, include gastric irritation, abdominal pain, nausea, vomiting, diarrhea, anorexia, constipation, aphthous ulcers, peptic ulcer, and xerostomia. Glossitis and dyspepsia have been reported with postmarketing use of captopril; a causal relationship to the drug has not been established.
Hypotension rarely occurs in patients receiving captopril to treat hypertension, but hypotensive symptoms have required discontinuation of the drug in 3.6% of patients with congestive heart failure. Excessive hypotension is more likely in patients who are salt/volume depleted (such as those treated vigorously with diuretics), patients with heart failure or those patients undergoing renal dialysis. Sinus tachycardia, chest pain (unspecified), and palpitations have been reported in 1% of patients. Other cardiovascular-related adverse events include: cardiac arrest, cerebrovascular accident/insufficiency, arrhythmia exacerbation, orthostatic hypotension, and syncope. Angina pectoris, myocardial infarction, Raynaud's syndrome, and congestive heart failure have each occurred in 0.2-0.3% of patients.
Cough has been reported in 0.5-2% of patients treated with captopril in clinical trials. ACE inhibition can result in the accumulation of kinins in the respiratory tract, sometimes causing a persistent, nonproductive cough. However, accumulation of kinins does not adequately explain the mechanism of ACE inhibitor-induced cough. Kinins have a very short plasma half-life, therapeutic doses of ACE inhibitors are usually not high enough to cause accumulation of circulating bradykinin, and there is a female preponderance of cases. Rather, evidence is growing that ACE inhibitor-induced cough may be related to substance P stimulation of C-fiber receptors in the respiratory tract. Dyspnea has been reported in about 0.5-2% of patients but did not appear at increased frequency compared to placebo or other treatments used in controlled trials. Other respiratory-related adverse events (incidence unknown) include: bronchospasm, eosinophilic pneumonia, and rhinitis.
A symptom complex has been reported during captopril therapy which may include a positive ANA, an elevated erythrocyte sedimentation rate, arthralgia/arthritis, myalgia, fever, vasculitis, eosinophilia and leukocytosis. Pruritus, without rash, occurs in about 2% of patients. Approximately 4-7% of patients receiving captopril experience a maculopapular rash accompanied by pruritus and erythema, and occasionally by fever, eosinophilia, and arthralgia. The rash is generally mild and disappears within a few days following dosage reduction. In some cases, another ACE inhibitor has been subsequently administered without sequelae. Photosensitivity has been reported. Between 7 and 10% of patients with skin rash have shown an eosinophilia and/or positive ANA titers. A reversible associated pemphigoid-like lesion, and photosensitivity, have also been reported. Flushing or pallor has been reported in 2-5% of patients. Erythema multiforme (including Stevens-Johnson syndrome) and exfoliative dermatitis have also been reported with captopril use.
ACE inhibitors have been associated with anaphylactoid reactions, likely due to their inhibitory effect on eicosanoid and polypeptide metabolism, including bradykinin metabolism. Angioedema, or angioneurotic edema, of the face, edema of the extremities, mucous membranes, tongue, lips, larynx (laryngeal edema), and glottis has occurred rarely during ACE inhibitor therapy but is reversible following discontinuance of the drug. Involvement of the upper respiratory tract can induce acute respiratory distress. The onset usually occurs within hours or at most 1 week after starting ACE inhibitor therapy, but may occur at any time during therapy. The mechanism is unknown but may involve drug-induced auto-antibodies, bradykinin accumulation, dysregulation of the complement system, or histamine. Black patients receiving ACE inhibitors have been reported to have a higher incidence of angioedema compared to non-black patients. If angioedema occurs during therapy with captopril, the drug should be discontinued immediately. Appropriate monitoring and therapy should be provided until signs and symptoms have resolved completely. Angioedema associated with laryngeal edema or tongue edema may be fatal. If there is involvement of the tongue, glottis or larynx, appropriate therapy (e.g., 0.3 to 0.5 ml subcutaneous epinephrine 1:1000) and/or measures to ensure a patent airway should be promptly provided. Even in those instances where swelling of only the tongue is involved, without respiratory distress, patients may require prolonged observation since treatment with antihistamines and corticosteroids may not be sufficient. Patients with involvement of the tongue, glottis or larynx are likely to experience airway obstruction, especially those with a history of airway surgery. Rarely, intestinal angioedema has been reported during post-marketing experience with ACE inhibitors. Patients with intestinal angioedema may present with abdominal pain (with or without nausea or vomiting). In some cases there is no prior history of facial angioedema and C-1 esterase levels are normal. Intestinal angioedema can be diagnosed by procedures including abdominal CT scan or ultrasound, or at surgery. Symptoms resolve after stopping the ACE inhibitor. Intestinal angioedema should be included in the differential diagnosis of patients receiving ACE inhibitors who present with abdominal pain.
Elevations in serum potassium have been observed in some patients treated with ACE inhibitors, including captopril. Patients at increased risk for the development of hyperkalemia include those with renal insufficiency, diabetes mellitus, and those using concomitant potassium-sparing diuretics, potassium supplements or potassium-containing salt substitutes, or other drugs associated with increases in serum potassium.
Rarely, ACE inhibitors have been associated with a syndrome that starts with cholestatic jaundice and progresses to fulminant hepatic necrosis (hepatic failure) and death. Discontinue captopril in patients who develop jaundice or marked elevated hepatic enzymes and provide appropriate medical follow-up. Hepatitis, cholestasis, and pancreatitis have been reported although an incidence or causal relationship cannot be accurately determined.
Due to the potential for teratogenesis, captopril should not be used during pregnancy. Drugs that affect the renin-angiotensin system have been associated with fetal and neonatal abnormalities when administered to women during the second or third trimesters of pregnancy. Adverse fetal and neonatal effects have included hypotension, neonatal skull hypoplasia, anuria, renal failure, oligohydramnios, and death. Oligohydramnios has been associated with fetal lung hypoplasia and skeletal deformations. If oliguria or hypotension occurs in a neonate with a history of in utero exposure to captopril, blood pressure and renal perfusion support may be required, as well as exchange transfusion or dialysis to reverse hypotension and/or support decreased renal function. Captopril, which crosses the placenta, has been removed from neonatal circulation by peritoneal dialysis with some clinical benefit, and theoretically may be removed by exchange transfusion, although there is no experience with the latter procedure.
Hyponatremia, particularly in patients receiving concomitant diuretic therapy or a low-sodium diet, may occur during captopril therapy.
Nervous system adverse reactions reported in 0.5-2% of patients receiving captopril, but not at a greater frequency than patients receiving placebo or other therapies in controlled trials, include dizziness, headache, malaise, fatigue, insomnia, and paresthesias. Ataxia, confusion, depression, nervousness, and drowsiness have been reported with post-marketing use of captopril; a causal relationship to the drug has not been established.
Alopecia was reported in 0.5-2% of patients receiving captopril, but not at a greater frequency than patients receiving placebo or other therapies in controlled trials. Asthenia, gynecomastia, myasthenia, and blurred vision have been reported with post-marketing use of captopril; a causal relationship to the drug has not been established.
Angiotensin-converting enzyme inhibitors (ACE inhibitors) hypersensitivity usually manifests as a result of alterations in kinin generation in sensitive individuals; there is no evidence of a specific immune-mediated reaction. However, such reactions can be potentially life-threatening, even if they are not true 'allergic' reactions. Captopril is contraindicated in patients with a history of ACE-inhibitor induced angioedema, and should not be used in patients with hereditary angioedema or idiopathic angioedema. Risk of angioedema may be higher in patients with a history of angioedema unrelated to ACE inhibitors. If angioedema occurs, ACE inhibitor therapy should be halted and appropriate treatment instituted. The incidence of ACE-inhibitor induced angioedema is higher in Black patients than non-Black patients. In addition, ACE inhibitors are less effective in lowering blood pressure in Black patients, including the African American population.
Use captopril with caution in patients with risk factors for hyperkalemia. ACE inhibitors can elevate serum potassium concentrations and could worsen pre-existing conditions. Hyperkalemia may be associated with serious cardiac arrhythmias. Risk factors for the development of hyperkalemia include renal insufficiency, diabetes mellitus, and the concomitant use of potassium-sparing diuretics, potassium supplements, and/or potassium-containing salt substitutes, which should be used cautiously, if at all, with captopril. Monitor patients with these risk factors closely for hyperkalemia. In a trial of type 1 diabetic patients with proteinuria, the incidence of withdrawal of treatment with captopril for hyperkalemia was 2%. In 2 trials of normotensive type 1 diabetic patients with microalbuminuria, no captopril group subjects experienced hyperkalemia. Dosage adjustment of captopril is recommended in patients with renal impairment or renal failure with a creatinine clearance (CrCl) 50 mL/minute or less; carefully monitor renal function and serum potassium. Treatment with ACE inhibitors has demonstrated favorable effects on the progression of renal disease in diabetic and nondiabetic patients; however, minor increases in BUN and serum creatinine may occur. These effects, more commonly reported in patients with renal artery stenosis or those receiving concomitant diuretic therapy, are usually reversible and are not considered a reason to withhold therapy unless accompanied by hyperkalemia. If captopril is initiated in patients with renal artery stenosis, renal function should be monitored during the first few weeks of therapy.
Captopril therapy can cause neutropenia or agranulocytosis. Patients with renal impairment, immunosuppression or receiving immunosuppressives, and patients with collagen-vascular disease (e.g., systemic lupus erythematosus (SLE) or scleroderma) or autoimmune disease are at a greater risk for developing these complications. Complete blood counts should be established prior to and during captopril therapy when administered to these patient populations. (Leukocyte count with differential should be obtained every 2 weeks during the first 3 months of therapy in all patients receiving captopril.) Captopril should be used with caution in patients with pre-existing bone marrow suppression.
Captopril is relatively contraindicated in patients who exhibit hypotension. Captopril can cause severe hypotension when administered to patients with hypovolemia or hyponatremia or to patients receiving diuretics. This effect is due at least in part to its anti-aldosterone action. Captopril should be used cautiously in patients with congestive heart failure (initial doses should be lower than in the treatment of hypertension) because of a greater risk of developing hypotension. Hypotension may aggravate ischemia in patients with coronary artery disease or cerebrovascular disease precipitating a myocardial infarction or cerebrovascular accident. Captopril should be used with caution in patients with aortic stenosis or hypertrophic cardiomyopathy. As with all vasodilators, ACE inhibitors should be given with caution to patients with obstruction in the outflow tract of the left ventricle.
Treatment with captopril may increase the risk of anaphylactoid reactions in patients undergoing hymenoptera venom (insect sting) allergy desensitization. Two patients undergoing desensitizing treatment with hymenoptera venom while receiving ACE inhibitors sustained life-threatening anaphylactoid reactions. In the same patients, these reactions were avoided when ACE inhibitors were temporarily withheld, but they reappeared upon inadvertent rechallenge. However, a retrospective analysis of 79 patients who underwent hymenoptera venom (insect sting) allergy desensitization did not show an association between ACE inhibitor therapy and increased frequency of systemic reactions to venom immunotherapy. Of 17 patients taking an ACE inhibitor while undergoing desensitization, none experienced a systemic reaction to venom immunotherapy; whereas, 13 of 62 patients not taking an ACE inhibitor experienced a systemic reaction during venom immunotherapy. Anaphylactoid reactions have been reported in patients taking ACE inhibitors (enalapril) who were receiving dialysis with high-flux membranes; the mechanism is unknown. When anaphylactoid symptoms such as nausea, abdominal cramps, burning, angioedema, shortness of breath or low blood pressure are recognized, the dialysis should be stopped and the patient should receive aggressive treatment for the hypersensitivity reaction. Anaphylactoid reactions have also occurred in patients undergoing low-density lipoprotein apheresis with dextran sulfate absorption (a procedure dependent upon devices not approved in the United States). Although a causal relationship to ACE inhibitor therapy has not been firmly established, treatment with captopril may increase the risk for anaphylactoid reactions during membrane exposure. ACE inhibitors may also precipitate low blood pressure in dialysis patients who are volume-depleted.
When used during human pregnancy during the second and third trimesters, captopril, like other angiotensin-converting enzyme (ACE) inhibitors, can cause injury and even death to the developing fetus. When pregnancy is detected, captopril should be discontinued as soon as possible. Women of child-bearing age should be made aware of the potential risk and ACE inhibitors should only be given after careful counseling and consideration of individual risks and benefits. When pregnancy is detected, ACE inhibitors should be discontinued as soon as possible and monitoring of the fetal development should be performed on a regular basis. Rarely (probably less often than once per every thousand pregnancies), no alternative to ACE inhibitors will be found. In these rare cases, the pregnant women should be apprised of the potential hazards to their fetuses, and serial ultrasound examinations should be performed to assess the intraamniotic environment. The reported adverse fetal and neonatal effects (e.g., hypotension, neonatal skull hypoplasia and craniofacial deformation, fetal limb contractures, hypoplastic lung development, anuria, oligohydramnios, reversible or irreversible renal failure, and death) have been reported during ACE inhibitor exposure during the second and third trimesters. An observational study based on Tennessee Medicaid data reported that the risk of congenital malformations is significantly increased during first-trimester exposure to ACE inhibitors. However, a much larger observational study (n = 465,754) found that the risk of birth defects was similar in babies exposed to ACE inhibitors during the first trimester, in those exposed to other antihypertensives during the first trimester, and in those whose mothers were hypertensive but were not treated. Newborns born to mothers with hypertension, either treated or untreated, had a higher risk of birth defects than those born to mothers without hypertension. The authors concluded that the presence of hypertension likely contributed to the development of birth defects rather than the use of medications. Further evaluation of teratogenicity data associated with ACE inhibitor exposure during pregnancy is ongoing. Closely observe neonates with histories of in utero exposure to captopril for hypotension, oliguria, and hyperkalemia. If oliguria or hypotension occurs, blood pressure and renal perfusion support may be required, as well as exchange transfusion or dialysis to reverse hypotension and/or support decreased renal function.
Concentrations of captopril in human milk are about 1% of those in maternal blood. Due to low levels in breast milk, guidelines generally consider captopril and enalapril to be compatible with breast-feeding unless high doses are required. Consider the benefits of breast-feeding, the risk of potential infant drug exposure, and the risk of an untreated or inadequately treated condition.
Infants, especially neonates, may be more susceptible to the adverse hemodynamic effects of captopril. Excessive, prolonged and unpredictable decreases in blood pressure and associated complications, including oliguria and seizures, have been reported.
Greater sensitivity to the hypotensive effects of captopril is possible in geriatric patients due to an age-related decline in renal function; monitor renal function and serum potassium.
For the treatment of hypertension:
Oral dosage:
Adults: 25 mg PO 2 to 3 times daily, initially. May increase dose to 50 mg PO 3 times daily after 1 to 2 weeks or 24 hours or less under continuous medical supervision, followed by 100 mg PO 2 to 3 times daily and 150 mg PO 2 to 3 times daily if further control is needed. Usual dose range: 12.5 to 150 mg/day in 2 to 3 divided doses. Max: 450 mg/day.
Children* and Adolescents*: 0.5 mg/kg/dose (Max: 25 mg/dose) PO 3 times daily, initially. May increase dose if further control is needed. Max: 6 mg/kg/day (up to 450 mg/day).
Infants*: 0.05 mg/kg/dose PO 1 to 4 times daily, initially. May increase dose if further control is needed. Max: 6 mg/kg/day. 0.05 to 0.3 mg/kg PO every 8 to 24 hours titrated to clinical response (Max: 2 mg/kg/dose and 6 mg/kg/day) has been recommended based on a study of captopril in 73 pediatric patients (age: 11 days to 15 years). A lower initial dose, slower dose titration, and close monitoring of blood pressure response is necessary, especially in infants younger than 2 months.
Neonates*: 0.01 to 0.1 mg/kg/dose PO every 8 to 24 hours, initially. May increase dose up to 0.5 mg/kg/dose PO every 6 to 24 hours if further control is needed. A lower initial dose, slower dose titration, and close monitoring of blood pressure response is necessary in neonatal patients due to the potential for a prolonged duration of action.
For the treatment of hypertensive urgency* or hypertensive emergency*:
Oral dosage:
Adults: 25 mg PO; may repeat every 30 minutes as needed.
Children and Adolescents: 0.5 mg/kg/dose (Initial Max: 25 mg/dose) PO 3 times daily, initially. Titrate to clinical response (Max: 6 mg/kg/day [Max: 450 mg/day]).
Infants: 0.05 mg/kg/dose PO 1 to 4 times daily, initially. Titrate to clinical response (Max: 6 mg/kg/day).
For the treatment of hypertension and the subsequent decline in renal function associated with scleroderma renal crisis (SRC)*:
Oral dosage:
Adults: No specific dosage guidelines are available. Results of a study published in 1990 revealed the efficacy of ACE inhibitors in slowing the decline of renal function in systemic sclerosis; however, no dosage range was provided.
For the treatment of heart failure:
Oral dosage:
Adults: 6.25 mg PO 3 times daily, initially. Increase the dose every 1 to 2 weeks to the highest dosage level tolerated. Usual Max: 150 mg/day. Most will have a satisfactory clinical improvement at 50 to 100 mg PO 3 times daily. When possible, delay any further increases in dosages above 50 mg PO 3 times daily for at least 2 weeks to determine if satisfactory response occurs. Max: 450 mg/day. Guidelines recommend an angiotensin-converting enzyme (ACE) inhibitor to reduce morbidity and mortality in persons with chronic reduced ejection fraction heart failure (HFrEF) when the use of an angiotensin receptor neprilysin inhibitor (ARNI) is not feasible. ACE inhibitors are not recommended as an alternative to an ARNI in persons with preserved ejection fraction heart failure (HFpEF) due to lack of demonstrated benefit.
Adolescents*: 6.25 to 12.5 mg PO 2 to 3 times daily, initially. Titrate to clinical response (Usual Max: 150 mg/day).
Children*: 0.1 to 2 mg/kg/dose (Initial Max: 6.25 to 12.5 mg/dose) PO 2 to 4 times daily, initially. Titrate to clinical response (Max: 6 mg/kg/day [Max: 150 mg/day]).
Infants*: 0.01 to 0.17 mg/kg/dose PO 3 times daily, initially. Titrate to clinical response to a usual maximum dose of 1.5 mg/kg/day. In a small retrospective study in infants (n = 20), captopril was initiated at 0.25 to 0.5 mg/kg/day PO divided 3 times daily and titrated to maximum doses of 0.8 to 2.5 mg/kg/day; however, lower initial and maximum doses have been recommended in infants due to concern for increased adverse effects at higher doses.
Neonates*: 0.01 to 0.03 mg/kg/dose PO 3 times daily, initially. Titrate to clinical response to a usual maximum dose of 1.5 mg/kg/day. In a retrospective review of neonates (n = 23) and infants (n = 20), captopril was initiated at 0.05 to 0.55 mg/kg/day PO divided 3 times daily and titrated to maximum doses of 0.2 to 2.3 mg/kg/day; however, lower initial and maximum doses have been recommended in neonates due to concern for increased adverse effects at higher doses.
For the treatment of left ventricular dysfunction postmyocardial infarction:
Oral dosage:
Adults: 6.25 to 12.5 mg PO 3 times daily, initially. Increase the dose to 25 mg PO 3 times daily over the next several days and then 50 mg PO 3 times daily over the next several weeks.
For the treatment of proteinuria associated with diabetic nephropathy or nephrotic syndrome*:
-for the treatment of proteinuria associated with diabetic nephropathy:
Oral dosage:
Adults: 12.5 to 25 mg PO 2 to 3 times daily, initially. Adjust dose based on blood pressure and serum creatinine and potassium concentrations every 2 to 4 weeks up to the maximum tolerated dose. Usual dose: 50 mg PO 3 times daily. Max: 450 mg/day in 2 or 3 divided doses. The FDA-approved dosage is 25 mg PO 3 times daily.
Children* and Adolescents*: Initial doses of 0.3 to 1 mg/kg/dose PO 3 times daily titrated to clinical response up to a maximum dose of 6 mg/kg/day (administered in 3 divided doses) have been successful in reducing proteinuria or microalbuminuria in small studies (n = 8 to 15) of patients with diabetes or nephrotic syndrome unresponsive to conventional therapy. Although a specific total mg maximum dose has not been clearly defined, do not exceed initial and final doses recommended for adult patients (e.g., 25 mg/dose for initial doses and usual maximum of 150 mg/day for the final dose).
-for the treatment of proteinuria associated with congenital nephrotic syndrome* or nephrotic syndrome*:
Oral dosage:
Children and Adolescents: Initial doses of 0.3 to 1 mg/kg/dose PO 3 times daily titrated to clinical response up to a maximum dose of 6 mg/kg/day (administered in 3 divided doses) have been successful in reducing proteinuria or microalbuminuria in small studies (n = 8 to 15) of patients with diabetes or nephrotic syndrome unresponsive to conventional therapy. Although a specific total mg maximum dose has not been clearly defined, do not exceed initial and final doses recommended for adult patients (e.g., 25 mg/dose for initial doses and usual maximum of 150 mg/day for the final dose).
Neonates and Infants: Initial doses of 0.1 to 0.25 mg/kg/dose PO every 8 hours titrated to clinical response (Max: 6 mg/kg/day) have been used in combination with indomethacin (0.3 to 3 mg/kg/day PO divided every 12 hours) and unilateral nephrectomy in a small observational study (n = 7) of patients with congenital nephrotic syndrome. Treatment resulted in statistically significant increases in plasma albumin and decreases in albumin infusions over the follow-up period of 36 to 88 months.
Maximum Dosage Limits:
-Adults
450 mg/day PO.
-Geriatric
450 mg/day PO.
-Adolescents
Safety and efficacy have not been established; however, doses up to 6 mg/kg/day PO (Max: 450 mg/day) have been used off-label.
-Children
Safety and efficacy have not been established; however, doses up to 6 mg/kg/day PO (Max: 450 mg/day) have been used off-label.
-Infants
Safety and efficacy have not been established; however, doses up to 6 mg/kg/day PO have been used off-label. A lower maximum of 1.5 mg/kg/day PO is recommended for congestive heart failure.
-Neonates
Safety and efficacy have not been established; however, doses up to 6 mg/kg/day PO have been used off-label. A lower maximum of 1.5 mg/kg/day PO is recommended for congestive heart failure.
Patients with Hepatic Impairment Dosing
No dosage adjustments are recommended for captopril in hepatic impairment.
Patients with Renal Impairment Dosing
CrCl more than 50 mL/minute: no dosage adjustment needed.
CrCl 10 to 50 mL/minute: reduce recommended dose by 25%.
CrCl less than 10 mL/minute: reduce recommended dose by 50%.
Intermittent hemodialysis
Captopril is significantly removed by dialysis; doses should be given after dialysis. For pediatric patients, an initial dose reduction of 50% is recommended. Evaluate and adjust dosage of captopril based on clinical response to therapy.
Peritoneal dialysis
Adult patients: Reduce the initial dose by 25%, then titrate to desired clinical effect.
Pediatric patients: Reduce the initial dose by 50%, then titrate to desired clinical effect.
Continuous renal replacement therapy (CRRT)
Reduce the initial dose by 25%, then titrate to desired clinical effect.
*non-FDA-approved indication
Acarbose: (Moderate) ACE inhibitors may enhance the hypoglycemic effects of insulin or other antidiabetic agents by improving insulin sensitivity. Patients receiving antidiabetic agents can become hypoglycemic if ACE inhibitors are administered concomitantly. Patients receiving these drugs concomitantly with antidiabetic agents should be monitored for changes in glycemic control.
Acetaminophen; Aspirin, ASA; Caffeine: (Moderate) Aspirin, ASA may reduce the vasodilatory efficacy of ACE inhibitors by inhibiting the synthesis of vasodilatory prostaglandins. This interaction has been documented primarily in heart failure patients. However, the established benefits of using aspirin in combination with an ACE inhibitor in patients with ischemic heart disease and left ventricular dysfunction generally outweigh this concern. Patients receiving concurrent salicylates and ACE inhibitor therapy should be monitored for antihypertensive or vasodilatory efficacy; the dose of the ACE inhibitor can be adjusted if indicated based on clinical evaluation.
Acetaminophen; Aspirin, ASA; Caffeine: (Moderate) Aspirin, ASA may reduce the vasodilatory efficacy of ACE inhibitors by inhibiting the synthesis of vasodilatory prostaglandins. This interaction has been documented primarily in heart failure patients. However, the established benefits of using aspirin in combination with an ACE inhibitor in patients with ischemic heart disease and left ventricular dysfunction generally outweigh this concern. Patients receiving concurrent salicylates and ACE inhibitor therapy should be monitored for antihypertensive or vasodilatory efficacy; the dose of the ACE inhibitor can be adjusted if indicated based on clinical evaluation.
Acetaminophen; Aspirin: (Moderate) Aspirin, ASA may reduce the vasodilatory efficacy of ACE inhibitors by inhibiting the synthesis of vasodilatory prostaglandins. This interaction has been documented primarily in heart failure patients. However, the established benefits of using aspirin in combination with an ACE inhibitor in patients with ischemic heart disease and left ventricular dysfunction generally outweigh this concern. Patients receiving concurrent salicylates and ACE inhibitor therapy should be monitored for antihypertensive or vasodilatory efficacy; the dose of the ACE inhibitor can be adjusted if indicated based on clinical evaluation.
Acetaminophen; Aspirin; Diphenhydramine: (Moderate) Aspirin, ASA may reduce the vasodilatory efficacy of ACE inhibitors by inhibiting the synthesis of vasodilatory prostaglandins. This interaction has been documented primarily in heart failure patients. However, the established benefits of using aspirin in combination with an ACE inhibitor in patients with ischemic heart disease and left ventricular dysfunction generally outweigh this concern. Patients receiving concurrent salicylates and ACE inhibitor therapy should be monitored for antihypertensive or vasodilatory efficacy; the dose of the ACE inhibitor can be adjusted if indicated based on clinical evaluation.
Acetaminophen; Chlorpheniramine; Dextromethorphan; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Well-controlled hypertensive patients receiving phenylephrine at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure (especially systolic hypertension) has been reported in some patients.
Acetaminophen; Chlorpheniramine; Dextromethorphan; Pseudoephedrine: (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Acetaminophen; Chlorpheniramine; Phenylephrine : (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Well-controlled hypertensive patients receiving phenylephrine at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure (especially systolic hypertension) has been reported in some patients.
Acetaminophen; Dextromethorphan; Guaifenesin; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Well-controlled hypertensive patients receiving phenylephrine at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure (especially systolic hypertension) has been reported in some patients.
Acetaminophen; Dextromethorphan; Guaifenesin; Pseudoephedrine: (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Acetaminophen; Dextromethorphan; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Well-controlled hypertensive patients receiving phenylephrine at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure (especially systolic hypertension) has been reported in some patients.
Acetaminophen; Dextromethorphan; Pseudoephedrine: (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Acetaminophen; Guaifenesin; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Well-controlled hypertensive patients receiving phenylephrine at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure (especially systolic hypertension) has been reported in some patients.
Acetaminophen; Ibuprofen: (Moderate) Monitor blood pressure and renal function periodically during concomitant angiotensin-converting enzyme (ACE) inhibitor and nonsteroidal anti-inflammatory drug (NSAID) use. The antihypertensive effect of ACE inhibitors may be diminished by NSAIDs. In persons who are elderly, volume-depleted, or with compromised renal function, coadministration of ACE inhibitors and NSAIDs may result in deterioration of renal function, including possible acute renal failure; these effects are usually reversible.
Acetaminophen; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Well-controlled hypertensive patients receiving phenylephrine at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure (especially systolic hypertension) has been reported in some patients.
Acetaminophen; Pseudoephedrine: (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Acrivastine; Pseudoephedrine: (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Alemtuzumab: (Moderate) Alemtuzumab may cause hypotension. Careful monitoring of blood pressure and hypotensive symptoms is recommended especially in patients with ischemic heart disease and in patients on antihypertensive agents.
Aliskiren: (Major) Aliskiren-containing products are contraindicated in combination with angiotensin-converting enzyme inhibitors (ACE inhibitors) in patients with diabetes mellitus. In general, avoid combined use of two renin-angiotensin-aldosterone system (RAAS) inhibitors, particularly in patients with CrCl less than 60 mL/minute. Combination therapy increases the risk for hyperkalemia, renal impairment, and other side effects. Most patients receiving a comination of two RAAS inhibitors, such as ACE inhibitors and aliskiren do not obtain any additional benefit compared to monotherapy. Closely monitor blood pressure, renal function, and electrolytes if aliskiren must be combined with another RAAS inhibitor. In the ALTITUDE trial, patients with type 2 diabetes and renal impairment, a population at high risk for cardiovascular and renal events, were given aliskiren in addition to ACE inhibitors or ARBs. The trial was stopped early because aliskiren was associated with an increased risk of non-fatal stroke, renal complications, hyperkalemia, and hypotension. In the Veterans Affairs Nephropathy in Diabetes (VA NEPHRON-D) trial, no additional benefit over monotherapy was seen in patients receiving the combination of losartan and lisinopril compared to monotherapy; however, there was an increased incidence of hyperkalemia and acute renal injury.
Aliskiren; Hydrochlorothiazide, HCTZ: (Major) Aliskiren-containing products are contraindicated in combination with angiotensin-converting enzyme inhibitors (ACE inhibitors) in patients with diabetes mellitus. In general, avoid combined use of two renin-angiotensin-aldosterone system (RAAS) inhibitors, particularly in patients with CrCl less than 60 mL/minute. Combination therapy increases the risk for hyperkalemia, renal impairment, and other side effects. Most patients receiving a comination of two RAAS inhibitors, such as ACE inhibitors and aliskiren do not obtain any additional benefit compared to monotherapy. Closely monitor blood pressure, renal function, and electrolytes if aliskiren must be combined with another RAAS inhibitor. In the ALTITUDE trial, patients with type 2 diabetes and renal impairment, a population at high risk for cardiovascular and renal events, were given aliskiren in addition to ACE inhibitors or ARBs. The trial was stopped early because aliskiren was associated with an increased risk of non-fatal stroke, renal complications, hyperkalemia, and hypotension. In the Veterans Affairs Nephropathy in Diabetes (VA NEPHRON-D) trial, no additional benefit over monotherapy was seen in patients receiving the combination of losartan and lisinopril compared to monotherapy; however, there was an increased incidence of hyperkalemia and acute renal injury. (Major) Discontinue the thiazide diuretic prior to starting captopril, if possible, or start captopril at the lower dose of 6.25 or 12.5 mg/day. Monitor blood pressure, particularly when doses are increased, and renal function during concomitant use. Concomitant use may increase the risk for hypotension or renal failure.
Alogliptin; Metformin: (Moderate) Monitor blood glucose during concomitant metformin and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Alogliptin; Pioglitazone: (Moderate) Monitor blood glucose during concomitant thiazolidinedione and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Alpha-glucosidase Inhibitors: (Moderate) ACE inhibitors may enhance the hypoglycemic effects of insulin or other antidiabetic agents by improving insulin sensitivity. Patients receiving antidiabetic agents can become hypoglycemic if ACE inhibitors are administered concomitantly. Patients receiving these drugs concomitantly with antidiabetic agents should be monitored for changes in glycemic control.
Alprostadil: (Minor) The concomitant use of systemic alprostadil injection and antihypertensive agents, such as angiotensin-converting enzyme inhibitors (ACE inhibitors), may cause additive hypotension. Caution is advised with this combination. Systemic drug interactions with the urethral suppository (MUSE) or alprostadil intracavernous injection are unlikely in most patients because low or undetectable amounts of the drug are found in the peripheral venous circulation following administration. In those men with significant corpora cavernosa venous leakage, hypotension might be more likely. Use caution with in-clinic dosing for erectile dysfunction (ED) and monitor for the effects on blood pressure. However, in clinical trials with alprostadil intracavernous injection, anti-hypertensive agents had no apparent effect on the safety and efficacy of alprostadil.
Aluminum Hydroxide: (Major) Antacids can decrease the GI absorption of captopril if administered simultaneously.
Aluminum Hydroxide; Magnesium Carbonate: (Major) Antacids can decrease the GI absorption of captopril if administered simultaneously.
Aluminum Hydroxide; Magnesium Hydroxide: (Major) Antacids can decrease the GI absorption of captopril if administered simultaneously.
Aluminum Hydroxide; Magnesium Hydroxide; Simethicone: (Major) Antacids can decrease the GI absorption of captopril if administered simultaneously.
Aluminum Hydroxide; Magnesium Trisilicate: (Major) Antacids can decrease the GI absorption of captopril if administered simultaneously.
Amifostine: (Major) Patients receiving angiotensin-converting enzyme inhibitors should be closely monitored during amifostine infusions due to additive effects. Patients receiving amifostine at doses recommended for chemotherapy should have antihypertensive therapy interrupted 24 hours preceding administration of amifostine. If the antihypertensive cannot be stopped, patients should not receive amifostine.
Amiloride: (Major) Amiloride should be used very cautiously with agents that have potential to induce hyperkalemia; serum potassium levels monitored when such agents are coadministered with amiloride. Simultaneous use of a potassium-sparing diuretic (e.g., amiloride) with angiotensin-converting enzyme inhibitors (ACE inhibitors) can increase the risk of hyperkalemia, especially in the presence of renal impairment (renal disease, elderly patients). These agents should be used with caution and serum potassium levels monitored when the substances are coadministered. The Beers Criteria recommends avoiding routine use of this combination in older adults; reserve this combination for patients with demonstrated hypokalemia while taking an ACE inhibitor.
Amiloride; Hydrochlorothiazide, HCTZ: (Major) Amiloride should be used very cautiously with agents that have potential to induce hyperkalemia; serum potassium levels monitored when such agents are coadministered with amiloride. Simultaneous use of a potassium-sparing diuretic (e.g., amiloride) with angiotensin-converting enzyme inhibitors (ACE inhibitors) can increase the risk of hyperkalemia, especially in the presence of renal impairment (renal disease, elderly patients). These agents should be used with caution and serum potassium levels monitored when the substances are coadministered. The Beers Criteria recommends avoiding routine use of this combination in older adults; reserve this combination for patients with demonstrated hypokalemia while taking an ACE inhibitor. (Major) Discontinue the thiazide diuretic prior to starting captopril, if possible, or start captopril at the lower dose of 6.25 or 12.5 mg/day. Monitor blood pressure, particularly when doses are increased, and renal function during concomitant use. Concomitant use may increase the risk for hypotension or renal failure.
Aminosalicylate sodium, Aminosalicylic acid: (Moderate) Aspirin, ASA may reduce the vasodilatory efficacy of ACE inhibitors by inhibiting the synthesis of vasodilatory prostaglandins. This interaction has been documented primarily in heart failure patients. However, the established benefits of using aspirin in combination with an ACE inhibitor in patients with ischemic heart disease and left ventricular dysfunction generally outweigh this concern. Patients receiving concurrent salicylates and ACE inhibitor therapy should be monitored for antihypertensive or vasodilatory efficacy; the dose of the ACE inhibitor can be adjusted if indicated based on clinical evaluation.
Amlodipine; Celecoxib: (Moderate) Monitor blood pressure and renal function periodically during concomitant angiotensin-converting enzyme (ACE) inhibitor and nonsteroidal anti-inflammatory drug (NSAID) use. The antihypertensive effect of ACE inhibitors may be diminished by NSAIDs. In persons who are elderly, volume-depleted, or with compromised renal function, coadministration of ACE inhibitors and NSAIDs may result in deterioration of renal function, including possible acute renal failure; these effects are usually reversible.
Amlodipine; Olmesartan: (Major) In general, avoid combined use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) due to lack of benefit with concomitant use in most patients. Closely monitor blood pressure, renal function, and electrolytes in patients on ACE inhibitors and ARBs. Dual blockade of the renin-angiotensin system with ACE inhibitors and ARBs is associated with increased risks of hypotension, syncope, hyperkalemia, and changes in renal function, including acute renal failure, compared to monotherapy.
Amlodipine; Valsartan: (Major) In general, avoid combined use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) due to lack of benefit with concomitant use in most patients. Closely monitor blood pressure, renal function, and electrolytes in patients on ACE inhibitors and ARBs. Dual blockade of the renin-angiotensin system with ACE inhibitors and ARBs is associated with increased risks of hypotension, syncope, hyperkalemia, and changes in renal function, including acute renal failure, compared to monotherapy.
Amlodipine; Valsartan; Hydrochlorothiazide, HCTZ: (Major) Discontinue the thiazide diuretic prior to starting captopril, if possible, or start captopril at the lower dose of 6.25 or 12.5 mg/day. Monitor blood pressure, particularly when doses are increased, and renal function during concomitant use. Concomitant use may increase the risk for hypotension or renal failure. (Major) In general, avoid combined use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) due to lack of benefit with concomitant use in most patients. Closely monitor blood pressure, renal function, and electrolytes in patients on ACE inhibitors and ARBs. Dual blockade of the renin-angiotensin system with ACE inhibitors and ARBs is associated with increased risks of hypotension, syncope, hyperkalemia, and changes in renal function, including acute renal failure, compared to monotherapy.
Amobarbital: (Moderate) Concurrent use of amobarbital with antihypertensive agents may lead to hypotension. Monitor for decreases in blood pressure during times of coadministration.
Amphetamine: (Minor) Amphetamines increase both systolic and diastolic blood pressure and may counteract the activity of some antihypertensive agents, like angiotensin-converting enzyme inhibitors (ACE inhibitors). Close monitoring of blood pressure is advised.
Amphetamine; Dextroamphetamine Salts: (Minor) Amphetamines increase both systolic and diastolic blood pressure and may counteract the activity of some antihypertensive agents, like angiotensin-converting enzyme inhibitors (ACE inhibitors). Close monitoring of blood pressure is advised.
Amphetamine; Dextroamphetamine: (Minor) Amphetamines increase both systolic and diastolic blood pressure and may counteract the activity of some antihypertensive agents, like angiotensin-converting enzyme inhibitors (ACE inhibitors). Close monitoring of blood pressure is advised.
Angiotensin II receptor antagonists: (Major) In general, avoid combined use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) due to lack of benefit with concomitant use in most patients. Closely monitor blood pressure, renal function, and electrolytes in patients on ACE inhibitors and ARBs. Dual blockade of the renin-angiotensin system with ACE inhibitors and ARBs is associated with increased risks of hypotension, syncope, hyperkalemia, and changes in renal function, including acute renal failure, compared to monotherapy.
Angiotensin II: (Moderate) Angiotensin converting enzyme inhibitors (ACE inhibitors) may increase the response to angiotensin II. Angiotensin II is a naturally occurring peptide hormone of the renin-angiotensin-aldosterone system (RAAS) that causes vasoconstriction and an increase in blood pressure. ACE inhibitors reduce the breakdown of angiotensin II.
Antacids: (Major) Antacids can decrease the GI absorption of captopril if administered simultaneously.
Apomorphine: (Moderate) Use of angiotensin-converting enzyme inhibitors (ACE inhibitors) and apomorphine together can increase the hypotensive effects of apomorphine. Monitor blood pressure regularly during use of this combination.
Apraclonidine: (Minor) Alpha blockers as a class may reduce heart rate and blood pressure. While no specific drug interactions have been identified with systemic agents and apraclonidine during clinical trials, it is theoretically possible that additive blood pressure reductions could occur when apraclonidine is combined with the use of antihypertensive agents. Patients using cardiovascular drugs concomitantly with apraclonidine should have their pulse and blood pressure monitored periodically.
Aprotinin: (Moderate) The manufacturer recommends using aprotinin cautiously in patients that are receiving drugs that can affect renal function, such as ACE inhibitors, as the risk of renal impairment may be increased.
Aripiprazole: (Minor) Aripiprazole may enhance the hypotensive effects of antihypertensive agents.
Articaine; Epinephrine: (Moderate) Antihypertensives, including angiotensin-converting enzyme inhibitors, antagonize the vasopressor effects of parenteral epinephrine.
Asenapine: (Moderate) Secondary to alpha-blockade, asenapine can produce vasodilation that may result in additive effects during concurrent use of antihypertensive agents. The potential reduction in blood pressure can precipitate orthostatic hypotension and associated dizziness, tachycardia, and syncope. If concurrent use of asenapine and antihypertensive agents is necessary, patients should be counseled on measures to prevent orthostatic hypotension, such as sitting on the edge of the bed for several minutes prior to standing in the morning and rising slowly from a seated position. Close monitoring of blood pressure is recommended until the full effects of the combination therapy are known.
Aspirin, ASA: (Moderate) Aspirin, ASA may reduce the vasodilatory efficacy of ACE inhibitors by inhibiting the synthesis of vasodilatory prostaglandins. This interaction has been documented primarily in heart failure patients. However, the established benefits of using aspirin in combination with an ACE inhibitor in patients with ischemic heart disease and left ventricular dysfunction generally outweigh this concern. Patients receiving concurrent salicylates and ACE inhibitor therapy should be monitored for antihypertensive or vasodilatory efficacy; the dose of the ACE inhibitor can be adjusted if indicated based on clinical evaluation.
Aspirin, ASA; Butalbital; Caffeine: (Moderate) Aspirin, ASA may reduce the vasodilatory efficacy of ACE inhibitors by inhibiting the synthesis of vasodilatory prostaglandins. This interaction has been documented primarily in heart failure patients. However, the established benefits of using aspirin in combination with an ACE inhibitor in patients with ischemic heart disease and left ventricular dysfunction generally outweigh this concern. Patients receiving concurrent salicylates and ACE inhibitor therapy should be monitored for antihypertensive or vasodilatory efficacy; the dose of the ACE inhibitor can be adjusted if indicated based on clinical evaluation.
Aspirin, ASA; Caffeine: (Moderate) Aspirin, ASA may reduce the vasodilatory efficacy of ACE inhibitors by inhibiting the synthesis of vasodilatory prostaglandins. This interaction has been documented primarily in heart failure patients. However, the established benefits of using aspirin in combination with an ACE inhibitor in patients with ischemic heart disease and left ventricular dysfunction generally outweigh this concern. Patients receiving concurrent salicylates and ACE inhibitor therapy should be monitored for antihypertensive or vasodilatory efficacy; the dose of the ACE inhibitor can be adjusted if indicated based on clinical evaluation.
Aspirin, ASA; Caffeine; Orphenadrine: (Moderate) Aspirin, ASA may reduce the vasodilatory efficacy of ACE inhibitors by inhibiting the synthesis of vasodilatory prostaglandins. This interaction has been documented primarily in heart failure patients. However, the established benefits of using aspirin in combination with an ACE inhibitor in patients with ischemic heart disease and left ventricular dysfunction generally outweigh this concern. Patients receiving concurrent salicylates and ACE inhibitor therapy should be monitored for antihypertensive or vasodilatory efficacy; the dose of the ACE inhibitor can be adjusted if indicated based on clinical evaluation.
Aspirin, ASA; Carisoprodol; Codeine: (Moderate) Aspirin, ASA may reduce the vasodilatory efficacy of ACE inhibitors by inhibiting the synthesis of vasodilatory prostaglandins. This interaction has been documented primarily in heart failure patients. However, the established benefits of using aspirin in combination with an ACE inhibitor in patients with ischemic heart disease and left ventricular dysfunction generally outweigh this concern. Patients receiving concurrent salicylates and ACE inhibitor therapy should be monitored for antihypertensive or vasodilatory efficacy; the dose of the ACE inhibitor can be adjusted if indicated based on clinical evaluation.
Aspirin, ASA; Citric Acid; Sodium Bicarbonate: (Moderate) Aspirin, ASA may reduce the vasodilatory efficacy of ACE inhibitors by inhibiting the synthesis of vasodilatory prostaglandins. This interaction has been documented primarily in heart failure patients. However, the established benefits of using aspirin in combination with an ACE inhibitor in patients with ischemic heart disease and left ventricular dysfunction generally outweigh this concern. Patients receiving concurrent salicylates and ACE inhibitor therapy should be monitored for antihypertensive or vasodilatory efficacy; the dose of the ACE inhibitor can be adjusted if indicated based on clinical evaluation.
Aspirin, ASA; Dipyridamole: (Moderate) Aspirin, ASA may reduce the vasodilatory efficacy of ACE inhibitors by inhibiting the synthesis of vasodilatory prostaglandins. This interaction has been documented primarily in heart failure patients. However, the established benefits of using aspirin in combination with an ACE inhibitor in patients with ischemic heart disease and left ventricular dysfunction generally outweigh this concern. Patients receiving concurrent salicylates and ACE inhibitor therapy should be monitored for antihypertensive or vasodilatory efficacy; the dose of the ACE inhibitor can be adjusted if indicated based on clinical evaluation.
Aspirin, ASA; Omeprazole: (Moderate) Aspirin, ASA may reduce the vasodilatory efficacy of ACE inhibitors by inhibiting the synthesis of vasodilatory prostaglandins. This interaction has been documented primarily in heart failure patients. However, the established benefits of using aspirin in combination with an ACE inhibitor in patients with ischemic heart disease and left ventricular dysfunction generally outweigh this concern. Patients receiving concurrent salicylates and ACE inhibitor therapy should be monitored for antihypertensive or vasodilatory efficacy; the dose of the ACE inhibitor can be adjusted if indicated based on clinical evaluation.
Aspirin, ASA; Oxycodone: (Moderate) Aspirin, ASA may reduce the vasodilatory efficacy of ACE inhibitors by inhibiting the synthesis of vasodilatory prostaglandins. This interaction has been documented primarily in heart failure patients. However, the established benefits of using aspirin in combination with an ACE inhibitor in patients with ischemic heart disease and left ventricular dysfunction generally outweigh this concern. Patients receiving concurrent salicylates and ACE inhibitor therapy should be monitored for antihypertensive or vasodilatory efficacy; the dose of the ACE inhibitor can be adjusted if indicated based on clinical evaluation.
Atenolol; Chlorthalidone: (Major) Discontinue the thiazide diuretic prior to starting captopril, if possible, or start captopril at the lower dose of 6.25 or 12.5 mg/day. Monitor blood pressure, particularly when doses are increased, and renal function during concomitant use. Concomitant use may increase the risk for hypotension or renal failure.
Auranofin: (Minor) Nitritoid reactions (facial flushing, diaphoresis, dizziness, nausea/vomiting, hypotension, tachycardia, syncope, and anaphylactic type reactions) or vasomotor reactions have been reported rarely in patients receiving injectable gold and concomitant ACE inhibitor therapy. Monitor closely for nitritoid reactions during co-therapy with gold and ACE inhibitor agents.
Azathioprine: (Major) The use of ACE inhibitors in hypertensive patients receiving azathioprine has been reported to induce anemia and severe leukopenia. This combination should be avoided where possible. When concurrent azathioprine and ACE inhibitor therapy is necessary, the patient should be monitored cautiously for potential myelosuppression.
Azilsartan: (Major) In general, avoid combined use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) due to lack of benefit with concomitant use in most patients. Closely monitor blood pressure, renal function, and electrolytes in patients on ACE inhibitors and ARBs. Dual blockade of the renin-angiotensin system with ACE inhibitors and ARBs is associated with increased risks of hypotension, syncope, hyperkalemia, and changes in renal function, including acute renal failure, compared to monotherapy.
Azilsartan; Chlorthalidone: (Major) Discontinue the thiazide diuretic prior to starting captopril, if possible, or start captopril at the lower dose of 6.25 or 12.5 mg/day. Monitor blood pressure, particularly when doses are increased, and renal function during concomitant use. Concomitant use may increase the risk for hypotension or renal failure. (Major) In general, avoid combined use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) due to lack of benefit with concomitant use in most patients. Closely monitor blood pressure, renal function, and electrolytes in patients on ACE inhibitors and ARBs. Dual blockade of the renin-angiotensin system with ACE inhibitors and ARBs is associated with increased risks of hypotension, syncope, hyperkalemia, and changes in renal function, including acute renal failure, compared to monotherapy.
Baclofen: (Moderate) Baclofen has been associated with hypotension. Concurrent use with baclofen and antihypertensive agents may result in additive hypotension. Dosage adjustments of the antihypertensive medication may be required.
Benazepril; Hydrochlorothiazide, HCTZ: (Major) Discontinue the thiazide diuretic prior to starting captopril, if possible, or start captopril at the lower dose of 6.25 or 12.5 mg/day. Monitor blood pressure, particularly when doses are increased, and renal function during concomitant use. Concomitant use may increase the risk for hypotension or renal failure.
Benzoic Acid; Hyoscyamine; Methenamine; Methylene Blue; Phenyl Salicylate: (Moderate) Aspirin, ASA may reduce the vasodilatory efficacy of ACE inhibitors by inhibiting the synthesis of vasodilatory prostaglandins. This interaction has been documented primarily in heart failure patients. However, the established benefits of using aspirin in combination with an ACE inhibitor in patients with ischemic heart disease and left ventricular dysfunction generally outweigh this concern. Patients receiving concurrent salicylates and ACE inhibitor therapy should be monitored for antihypertensive or vasodilatory efficacy; the dose of the ACE inhibitor can be adjusted if indicated based on clinical evaluation.
Benzphetamine: (Minor) Benzphetamine may increase both systolic and diastolic blood pressure and may counteract the activity of some antihypertensive agents, like angiotensin-converting enzyme inhibitors (ACE inhibitors). Close monitoring of blood pressure is advised.
Bexagliflozin: (Moderate) Monitor blood glucose during concomitant SGLT2 inhibitor and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Bismuth Subsalicylate: (Moderate) Aspirin, ASA may reduce the vasodilatory efficacy of ACE inhibitors by inhibiting the synthesis of vasodilatory prostaglandins. This interaction has been documented primarily in heart failure patients. However, the established benefits of using aspirin in combination with an ACE inhibitor in patients with ischemic heart disease and left ventricular dysfunction generally outweigh this concern. Patients receiving concurrent salicylates and ACE inhibitor therapy should be monitored for antihypertensive or vasodilatory efficacy; the dose of the ACE inhibitor can be adjusted if indicated based on clinical evaluation.
Bismuth Subsalicylate; Metronidazole; Tetracycline: (Moderate) Aspirin, ASA may reduce the vasodilatory efficacy of ACE inhibitors by inhibiting the synthesis of vasodilatory prostaglandins. This interaction has been documented primarily in heart failure patients. However, the established benefits of using aspirin in combination with an ACE inhibitor in patients with ischemic heart disease and left ventricular dysfunction generally outweigh this concern. Patients receiving concurrent salicylates and ACE inhibitor therapy should be monitored for antihypertensive or vasodilatory efficacy; the dose of the ACE inhibitor can be adjusted if indicated based on clinical evaluation.
Bisoprolol; Hydrochlorothiazide, HCTZ: (Major) Discontinue the thiazide diuretic prior to starting captopril, if possible, or start captopril at the lower dose of 6.25 or 12.5 mg/day. Monitor blood pressure, particularly when doses are increased, and renal function during concomitant use. Concomitant use may increase the risk for hypotension or renal failure.
Brexpiprazole: (Moderate) Due to brexpiprazole's antagonism at alpha 1-adrenergic receptors, the drug may enhance the hypotensive effects of alpha-blockers and other antihypertensive agents.
Brompheniramine; Dextromethorphan; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Well-controlled hypertensive patients receiving phenylephrine at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure (especially systolic hypertension) has been reported in some patients.
Brompheniramine; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Well-controlled hypertensive patients receiving phenylephrine at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure (especially systolic hypertension) has been reported in some patients.
Brompheniramine; Pseudoephedrine: (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Brompheniramine; Pseudoephedrine; Dextromethorphan: (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Bumetanide: (Major) Discontinue the loop diuretic prior to starting captopril, if possible, or start captopril at the lower dose of 6.25 or 12.5 mg/day. Monitor blood pressure and renal function during concomitant use, particularly when doses are increased. Concomitant use may increase the risk for hypotension or renal failure.
Bupivacaine; Epinephrine: (Moderate) Antihypertensives, including angiotensin-converting enzyme inhibitors, antagonize the vasopressor effects of parenteral epinephrine.
Bupivacaine; Meloxicam: (Moderate) Monitor blood pressure and renal function periodically during concomitant angiotensin-converting enzyme (ACE) inhibitor and nonsteroidal anti-inflammatory drug (NSAID) use. The antihypertensive effect of ACE inhibitors may be diminished by NSAIDs. In persons who are elderly, volume-depleted, or with compromised renal function, coadministration of ACE inhibitors and NSAIDs may result in deterioration of renal function, including possible acute renal failure; these effects are usually reversible.
Butalbital; Aspirin; Caffeine; Codeine: (Moderate) Aspirin, ASA may reduce the vasodilatory efficacy of ACE inhibitors by inhibiting the synthesis of vasodilatory prostaglandins. This interaction has been documented primarily in heart failure patients. However, the established benefits of using aspirin in combination with an ACE inhibitor in patients with ischemic heart disease and left ventricular dysfunction generally outweigh this concern. Patients receiving concurrent salicylates and ACE inhibitor therapy should be monitored for antihypertensive or vasodilatory efficacy; the dose of the ACE inhibitor can be adjusted if indicated based on clinical evaluation.
Cabergoline: (Moderate) Cabergoline should be used cautiously with antihypertensive agents, including angiotensin-converting enzyme inhibitors. Cabergoline has been associated with hypotension. Initial doses of cabergoline higher than 1 mg may produce orthostatic hypotension. It may be advisable to monitor blood pressure.
Calcium Carbonate: (Major) Antacids can decrease the GI absorption of captopril if administered simultaneously.
Calcium Carbonate; Famotidine; Magnesium Hydroxide: (Major) Antacids can decrease the GI absorption of captopril if administered simultaneously.
Calcium Carbonate; Magnesium Hydroxide: (Major) Antacids can decrease the GI absorption of captopril if administered simultaneously.
Calcium Carbonate; Magnesium Hydroxide; Simethicone: (Major) Antacids can decrease the GI absorption of captopril if administered simultaneously.
Calcium Carbonate; Simethicone: (Major) Antacids can decrease the GI absorption of captopril if administered simultaneously.
Calcium Phosphate, Supersaturated: (Moderate) Concomitant use of medicines with potential to alter renal perfusion or function such as angiotensin-converting enzyme inhibitors, may increase the risk of acute phosphate nephropathy in patients taking sodium phosphate monobasic monohydrate; sodium phosphate dibasic anhydrous.
Calcium; Vitamin D: (Major) Antacids can decrease the GI absorption of captopril if administered simultaneously.
Canagliflozin: (Moderate) Monitor blood glucose during concomitant SGLT2 inhibitor and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Canagliflozin; Metformin: (Moderate) Monitor blood glucose during concomitant metformin and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia. (Moderate) Monitor blood glucose during concomitant SGLT2 inhibitor and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Candesartan: (Major) In general, avoid combined use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) due to lack of benefit with concomitant use in most patients. Closely monitor blood pressure, renal function, and electrolytes in patients on ACE inhibitors and ARBs. Dual blockade of the renin-angiotensin system with ACE inhibitors and ARBs is associated with increased risks of hypotension, syncope, hyperkalemia, and changes in renal function, including acute renal failure, compared to monotherapy.
Candesartan; Hydrochlorothiazide, HCTZ: (Major) Discontinue the thiazide diuretic prior to starting captopril, if possible, or start captopril at the lower dose of 6.25 or 12.5 mg/day. Monitor blood pressure, particularly when doses are increased, and renal function during concomitant use. Concomitant use may increase the risk for hypotension or renal failure. (Major) In general, avoid combined use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) due to lack of benefit with concomitant use in most patients. Closely monitor blood pressure, renal function, and electrolytes in patients on ACE inhibitors and ARBs. Dual blockade of the renin-angiotensin system with ACE inhibitors and ARBs is associated with increased risks of hypotension, syncope, hyperkalemia, and changes in renal function, including acute renal failure, compared to monotherapy.
Captopril; Hydrochlorothiazide, HCTZ: (Major) Discontinue the thiazide diuretic prior to starting captopril, if possible, or start captopril at the lower dose of 6.25 or 12.5 mg/day. Monitor blood pressure, particularly when doses are increased, and renal function during concomitant use. Concomitant use may increase the risk for hypotension or renal failure.
Carbidopa; Levodopa: (Moderate) Concomitant use of antihypertensive agents with levodopa can result in additive hypotensive effects.
Carbidopa; Levodopa; Entacapone: (Moderate) Concomitant use of antihypertensive agents with levodopa can result in additive hypotensive effects.
Cariprazine: (Moderate) Orthostatic vital signs should be monitored in patients who are at risk for hypotension, such as those receiving cariprazine in combination with antihypertensive agents. Atypical antipsychotics may cause orthostatic hypotension and syncope, most commonly during treatment initiation and dosage increases. Patients should be informed about measures to prevent orthostatic hypotension, such as sitting on the edge of the bed for several minutes prior to standing in the morning, or rising slowly from a seated position. Consider a cariprazine dose reduction if hypotension occurs.
Celecoxib: (Moderate) Monitor blood pressure and renal function periodically during concomitant angiotensin-converting enzyme (ACE) inhibitor and nonsteroidal anti-inflammatory drug (NSAID) use. The antihypertensive effect of ACE inhibitors may be diminished by NSAIDs. In persons who are elderly, volume-depleted, or with compromised renal function, coadministration of ACE inhibitors and NSAIDs may result in deterioration of renal function, including possible acute renal failure; these effects are usually reversible.
Celecoxib; Tramadol: (Moderate) Monitor blood pressure and renal function periodically during concomitant angiotensin-converting enzyme (ACE) inhibitor and nonsteroidal anti-inflammatory drug (NSAID) use. The antihypertensive effect of ACE inhibitors may be diminished by NSAIDs. In persons who are elderly, volume-depleted, or with compromised renal function, coadministration of ACE inhibitors and NSAIDs may result in deterioration of renal function, including possible acute renal failure; these effects are usually reversible.
Cetirizine; Pseudoephedrine: (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Chlophedianol; Dexchlorpheniramine; Pseudoephedrine: (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Chloroprocaine: (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents.
Chlorothiazide: (Major) Discontinue the thiazide diuretic prior to starting captopril, if possible, or start captopril at the lower dose of 6.25 or 12.5 mg/day. Monitor blood pressure, particularly when doses are increased, and renal function during concomitant use. Concomitant use may increase the risk for hypotension or renal failure.
Chlorpheniramine; Dextromethorphan; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Well-controlled hypertensive patients receiving phenylephrine at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure (especially systolic hypertension) has been reported in some patients.
Chlorpheniramine; Dextromethorphan; Pseudoephedrine: (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Chlorpheniramine; Ibuprofen; Pseudoephedrine: (Moderate) Monitor blood pressure and renal function periodically during concomitant angiotensin-converting enzyme (ACE) inhibitor and nonsteroidal anti-inflammatory drug (NSAID) use. The antihypertensive effect of ACE inhibitors may be diminished by NSAIDs. In persons who are elderly, volume-depleted, or with compromised renal function, coadministration of ACE inhibitors and NSAIDs may result in deterioration of renal function, including possible acute renal failure; these effects are usually reversible. (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Chlorpheniramine; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Well-controlled hypertensive patients receiving phenylephrine at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure (especially systolic hypertension) has been reported in some patients.
Chlorpheniramine; Pseudoephedrine: (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Chlorthalidone: (Major) Discontinue the thiazide diuretic prior to starting captopril, if possible, or start captopril at the lower dose of 6.25 or 12.5 mg/day. Monitor blood pressure, particularly when doses are increased, and renal function during concomitant use. Concomitant use may increase the risk for hypotension or renal failure.
Choline Salicylate; Magnesium Salicylate: (Moderate) Aspirin, ASA may reduce the vasodilatory efficacy of ACE inhibitors by inhibiting the synthesis of vasodilatory prostaglandins. This interaction has been documented primarily in heart failure patients. However, the established benefits of using aspirin in combination with an ACE inhibitor in patients with ischemic heart disease and left ventricular dysfunction generally outweigh this concern. Patients receiving concurrent salicylates and ACE inhibitor therapy should be monitored for antihypertensive or vasodilatory efficacy; the dose of the ACE inhibitor can be adjusted if indicated based on clinical evaluation.
Citric Acid; Potassium Citrate; Sodium Citrate: (Moderate) Monitor serum potassium concentrations closely if potassium supplements and angiotensin-converting enzyme inhibitors (ACE inhibitors) are used together. Concomitant use may increase the risk of hyperkalemia.
Clozapine: (Moderate) Lisinopril may decrease the renal elimination of clozapine and metabolites. Clozapine toxicity, including irritability, anger, insomnia, nightmares and sialorrhea may occur. The mechanism of this interaction is unclear; however, as lisinopril does not undergo metabolism, cytochrome P450 enzyme involvement is unlikely. It is speculated that a decrease in renal elimination of clozapine occurs due to a lisinopril-induced reduction in glomerular filtration rate (GFR). Plasma clozapine concentrations should be measured carefully during concomitant lisinopril therapy; another antihypertensive class may need to be selected. In addition, clozapine used concomitantly with the antihypertensive agents can increase the risk and severity of hypotension by potentiating the effect of the antihypertensive drug.
Cocaine: (Major) Use of cocaine with antihypertensive agents may increase the antihypertensive effects of the antihypertensive medications or may potentiate cocaine-induced sympathetic stimulation.
Codeine; Guaifenesin; Pseudoephedrine: (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Codeine; Phenylephrine; Promethazine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Well-controlled hypertensive patients receiving phenylephrine at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure (especially systolic hypertension) has been reported in some patients.
Co-Enzyme Q10, Ubiquinone: (Moderate) Co-enzyme Q10, ubiquinone (CoQ10) may lower blood pressure. CoQ10 use in combination with antihypertensive agents may lead to additional reductions in blood pressure in some individuals. Patients who choose to take CoQ10 concurrently with antihypertensive medications should receive periodic blood pressure monitoring. Patients should be advised to inform their prescriber of their use of CoQ10.
Cyclophosphamide: (Moderate) Closely monitor complete blood counts if coadministration of cyclophosphamide with angiotensin-converting enzyme inhibitors (ACE inhibitors) is necessary as there is an increased risk of hematologic toxicity (specifically leukopenia) and immunosuppression.
Cyclosporine: (Moderate) Several cases of acute renal failure have been associated with the addition of angiotensin-converting enzyme (ACE) inhibitors to cyclosporine therapy in renal transplant patients. In response to cyclosporine-induced renal afferent vasoconstriction and glomerular hypoperfusion, angiotensin II is required to maintain an adequate glomerular filtration rate. Inhibition of ACE could reduce renal function acutely. Also, cyclosporine can cause hyperkalemia, and inhibition of angiotensin II leads to reduced aldosterone concentrations, which can increase the serum potassium concentration. Closely monitor renal function and serum potassium concentrations in patients receiving cyclosporine concurrently with ACE inhibitors or potassium salts.
Dapagliflozin: (Moderate) Monitor blood glucose during concomitant SGLT2 inhibitor and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Dapagliflozin; Metformin: (Moderate) Monitor blood glucose during concomitant metformin and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia. (Moderate) Monitor blood glucose during concomitant SGLT2 inhibitor and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Dapagliflozin; Saxagliptin: (Moderate) Monitor blood glucose during concomitant SGLT2 inhibitor and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Desloratadine; Pseudoephedrine: (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Dexbrompheniramine; Pseudoephedrine: (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Dexchlorpheniramine; Dextromethorphan; Pseudoephedrine: (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Dexmethylphenidate: (Moderate) Periodic evaluation of blood pressure is advisable during concurrent use of methylphenidate derivatives and antihypertensive agents, particularly during initial coadministration and after dosage increases of methylphenidate derivatives. Methylphenidate derivatives can reduce the hypotensive effect of antihypertensive agents such as angiotensin-converting enzyme inhibitors.
Dextroamphetamine: (Minor) Amphetamines increase both systolic and diastolic blood pressure and may counteract the activity of some antihypertensive agents, like angiotensin-converting enzyme inhibitors (ACE inhibitors). Close monitoring of blood pressure is advised.
Dextromethorphan; Diphenhydramine; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Well-controlled hypertensive patients receiving phenylephrine at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure (especially systolic hypertension) has been reported in some patients.
Dextromethorphan; Guaifenesin; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Well-controlled hypertensive patients receiving phenylephrine at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure (especially systolic hypertension) has been reported in some patients.
Dextromethorphan; Guaifenesin; Pseudoephedrine: (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Dextromethorphan; Quinidine: (Moderate) Quinidine can decrease blood pressure and should be used cautiously in patients receiving antihypertensive agents due to the potential for additive hypotension.
Diazoxide: (Moderate) Additive hypotensive effects can occur with the concomitant administration of diazoxide with other antihypertensive agents. This interaction can be therapeutically advantageous, but dosages must be adjusted accordingly. The manufacturer advises that IV diazoxide should not be administered to patients within 6 hours of receiving other antihypertensive agents.
Diclofenac: (Moderate) Monitor blood pressure and renal function periodically during concomitant angiotensin-converting enzyme (ACE) inhibitor and nonsteroidal anti-inflammatory drug (NSAID) use. The antihypertensive effect of ACE inhibitors may be diminished by NSAIDs. In persons who are elderly, volume-depleted, or with compromised renal function, coadministration of ACE inhibitors and NSAIDs may result in deterioration of renal function, including possible acute renal failure; these effects are usually reversible.
Diclofenac; Misoprostol: (Moderate) Monitor blood pressure and renal function periodically during concomitant angiotensin-converting enzyme (ACE) inhibitor and nonsteroidal anti-inflammatory drug (NSAID) use. The antihypertensive effect of ACE inhibitors may be diminished by NSAIDs. In persons who are elderly, volume-depleted, or with compromised renal function, coadministration of ACE inhibitors and NSAIDs may result in deterioration of renal function, including possible acute renal failure; these effects are usually reversible.
Diethylpropion: (Major) Diethylpropion has vasopressor effects and may limit the benefit of angiotensin-converting enzyme inhibitors. Although leading drug interaction texts differ in the potential for an interaction between diethylpropion and this group of antihypertensive agents, these effects are likely to be clinically significant and have been described in hypertensive patients on these medications.
Diflunisal: (Moderate) Monitor blood pressure and renal function periodically during concomitant angiotensin-converting enzyme (ACE) inhibitor and nonsteroidal anti-inflammatory drug (NSAID) use. The antihypertensive effect of ACE inhibitors may be diminished by NSAIDs. In persons who are elderly, volume-depleted, or with compromised renal function, coadministration of ACE inhibitors and NSAIDs may result in deterioration of renal function, including possible acute renal failure; these effects are usually reversible.
Digoxin: (Major) Coadministration of digoxin and captopril increases the serum concentration and AUC of digoxin by 58% and 39%, respectively. However, captopril and digoxin are administered together in patients with congestive heart failure. Measure serum digoxin concentrations before initiating captopril. Reduce digoxin concentrations by decreasing the digoxin dose by approximately 30-50% or by modifying the dosing frequency and continue monitoring. In addition, caution should be exercised when administering digoxin with drugs that may cause a significant deterioration in renal function including angiotensin-converting enzyme inhibitors (ACE inhibitors). A decline in glomerular filtration or tubular secretion may impair the excretion of digoxin. Close monitoring of serum digoxin concentrations is essential to avoid enhanced toxicity.
Diphenhydramine; Ibuprofen: (Moderate) Monitor blood pressure and renal function periodically during concomitant angiotensin-converting enzyme (ACE) inhibitor and nonsteroidal anti-inflammatory drug (NSAID) use. The antihypertensive effect of ACE inhibitors may be diminished by NSAIDs. In persons who are elderly, volume-depleted, or with compromised renal function, coadministration of ACE inhibitors and NSAIDs may result in deterioration of renal function, including possible acute renal failure; these effects are usually reversible.
Diphenhydramine; Naproxen: (Moderate) Monitor blood pressure and renal function periodically during concomitant angiotensin-converting enzyme (ACE) inhibitor and nonsteroidal anti-inflammatory drug (NSAID) use. The antihypertensive effect of ACE inhibitors may be diminished by NSAIDs. In persons who are elderly, volume-depleted, or with compromised renal function, coadministration of ACE inhibitors and NSAIDs may result in deterioration of renal function, including possible acute renal failure; these effects are usually reversible.
Diphenhydramine; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Well-controlled hypertensive patients receiving phenylephrine at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure (especially systolic hypertension) has been reported in some patients.
Drospirenone: (Moderate) Drospirenone has antimineralocorticoid effects and may increase serum potassium. The concurrent use of ACE inhibitors may increase the risk of hyperkalemia, especially in the presence of renal impairment. Monitor serum potassium during the 1st month of drospirenone treatment if an Angiotensin-Converting Enzyme inhibitor (ACE inhibitor) is used concurrently and thereafter as clinically indicated. Also monitor for any changes in blood pressure, fluid retention, or renal function.
Drospirenone; Estetrol: (Moderate) Drospirenone has antimineralocorticoid effects and may increase serum potassium. The concurrent use of ACE inhibitors may increase the risk of hyperkalemia, especially in the presence of renal impairment. Monitor serum potassium during the 1st month of drospirenone treatment if an Angiotensin-Converting Enzyme inhibitor (ACE inhibitor) is used concurrently and thereafter as clinically indicated. Also monitor for any changes in blood pressure, fluid retention, or renal function.
Drospirenone; Estradiol: (Moderate) Drospirenone has antimineralocorticoid effects and may increase serum potassium. The concurrent use of ACE inhibitors may increase the risk of hyperkalemia, especially in the presence of renal impairment. Monitor serum potassium during the 1st month of drospirenone treatment if an Angiotensin-Converting Enzyme inhibitor (ACE inhibitor) is used concurrently and thereafter as clinically indicated. Also monitor for any changes in blood pressure, fluid retention, or renal function.
Drospirenone; Ethinyl Estradiol: (Moderate) Drospirenone has antimineralocorticoid effects and may increase serum potassium. The concurrent use of ACE inhibitors may increase the risk of hyperkalemia, especially in the presence of renal impairment. Monitor serum potassium during the 1st month of drospirenone treatment if an Angiotensin-Converting Enzyme inhibitor (ACE inhibitor) is used concurrently and thereafter as clinically indicated. Also monitor for any changes in blood pressure, fluid retention, or renal function.
Drospirenone; Ethinyl Estradiol; Levomefolate: (Moderate) Drospirenone has antimineralocorticoid effects and may increase serum potassium. The concurrent use of ACE inhibitors may increase the risk of hyperkalemia, especially in the presence of renal impairment. Monitor serum potassium during the 1st month of drospirenone treatment if an Angiotensin-Converting Enzyme inhibitor (ACE inhibitor) is used concurrently and thereafter as clinically indicated. Also monitor for any changes in blood pressure, fluid retention, or renal function.
Dulaglutide: (Moderate) Monitor blood glucose during concomitant incretin mimetic and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Duloxetine: (Moderate) Orthostatic hypotension and syncope have been reported during duloxetine administration. The concurrent administration of antihypertensive agents and duloxetine may increase the risk of hypotension. Monitor blood pressure if the combination is necessary.
Empagliflozin: (Moderate) Monitor blood glucose during concomitant SGLT2 inhibitor and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Empagliflozin; Linagliptin: (Moderate) Monitor blood glucose during concomitant SGLT2 inhibitor and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Empagliflozin; Linagliptin; Metformin: (Moderate) Monitor blood glucose during concomitant metformin and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia. (Moderate) Monitor blood glucose during concomitant SGLT2 inhibitor and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Empagliflozin; Metformin: (Moderate) Monitor blood glucose during concomitant metformin and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia. (Moderate) Monitor blood glucose during concomitant SGLT2 inhibitor and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Enalapril; Hydrochlorothiazide, HCTZ: (Major) Discontinue the thiazide diuretic prior to starting captopril, if possible, or start captopril at the lower dose of 6.25 or 12.5 mg/day. Monitor blood pressure, particularly when doses are increased, and renal function during concomitant use. Concomitant use may increase the risk for hypotension or renal failure.
Entecavir: (Moderate) Because entecavir is primarily eliminated by the kidneys and ACE inhibitors can affect renal function, concurrent administration with ACE inhibitors may increase the serum concentrations of entecavir and adverse events. Monitor for adverse effects when these drugs are coadministered.
Ephedrine: (Major) The cardiovascular effects of sympathomimetics, such as ephedrine, may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Blood pressure and heart rates should be monitored closely to confirm that the desired antihypertensive effect is achieved.
Ephedrine; Guaifenesin: (Major) The cardiovascular effects of sympathomimetics, such as ephedrine, may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Blood pressure and heart rates should be monitored closely to confirm that the desired antihypertensive effect is achieved.
Epinephrine: (Moderate) Antihypertensives, including angiotensin-converting enzyme inhibitors, antagonize the vasopressor effects of parenteral epinephrine.
Eplerenone: (Major) Monitor serum potassium and serum creatinine concentrations within 3 to 7 days of initiating coadministration of eplerenone and angiotensin-converting enzyme (ACE) inhibitors. Hyperkalemia risk is increased when eplerenone is used with ACE inhibitors. Patients who develop hyperkalemia may continue eplerenone with proper dose adjustment; eplerenone dose reduction decreases potassium concentrations.
Eprosartan: (Major) In general, avoid combined use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) due to lack of benefit with concomitant use in most patients. Closely monitor blood pressure, renal function, and electrolytes in patients on ACE inhibitors and ARBs. Dual blockade of the renin-angiotensin system with ACE inhibitors and ARBs is associated with increased risks of hypotension, syncope, hyperkalemia, and changes in renal function, including acute renal failure, compared to monotherapy.
Eprosartan; Hydrochlorothiazide, HCTZ: (Major) Discontinue the thiazide diuretic prior to starting captopril, if possible, or start captopril at the lower dose of 6.25 or 12.5 mg/day. Monitor blood pressure, particularly when doses are increased, and renal function during concomitant use. Concomitant use may increase the risk for hypotension or renal failure. (Major) In general, avoid combined use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) due to lack of benefit with concomitant use in most patients. Closely monitor blood pressure, renal function, and electrolytes in patients on ACE inhibitors and ARBs. Dual blockade of the renin-angiotensin system with ACE inhibitors and ARBs is associated with increased risks of hypotension, syncope, hyperkalemia, and changes in renal function, including acute renal failure, compared to monotherapy.
Ertugliflozin: (Moderate) Monitor blood glucose during concomitant SGLT2 inhibitor and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Ertugliflozin; Metformin: (Moderate) Monitor blood glucose during concomitant metformin and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia. (Moderate) Monitor blood glucose during concomitant SGLT2 inhibitor and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Ertugliflozin; Sitagliptin: (Moderate) Monitor blood glucose during concomitant SGLT2 inhibitor and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Estradiol: (Minor) Estrogens can induce fluid retention and may increase blood pressure in some patients; patients who are receiving antihypertensive agents concurrently with hormonal contraceptives should be monitored for antihypertensive effectiveness.
Ethacrynic Acid: (Major) Discontinue the loop diuretic prior to starting captopril, if possible, or start captopril at the lower dose of 6.25 or 12.5 mg/day. Monitor blood pressure and renal function during concomitant use, particularly when doses are increased. Concomitant use may increase the risk for hypotension or renal failure.
Ethiodized Oil: (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.
Etodolac: (Moderate) Monitor blood pressure and renal function periodically during concomitant angiotensin-converting enzyme (ACE) inhibitor and nonsteroidal anti-inflammatory drug (NSAID) use. The antihypertensive effect of ACE inhibitors may be diminished by NSAIDs. In persons who are elderly, volume-depleted, or with compromised renal function, coadministration of ACE inhibitors and NSAIDs may result in deterioration of renal function, including possible acute renal failure; these effects are usually reversible.
Etomidate: (Moderate) General anesthetics can potentiate the hypotensive effects of antihypertensive agents.
Everolimus: (Major) Avoid coadministration of everolimus with angiotensin-converting enzyme inhibitors (ACE inhibitors) as the risk of angioedema, with or without respiratory impairment, may be increased. In a pooled analysis of randomized, double-blind oncology clinical trials, angioedema was reported in 6.8% of patients receiving concomitant everolimus and ACE inhibitor therapy, compared to 1.3% of patients with an ACE inhibitor alone.
Exenatide: (Moderate) Monitor blood glucose during concomitant incretin mimetic and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Fenoprofen: (Moderate) Monitor blood pressure and renal function periodically during concomitant angiotensin-converting enzyme (ACE) inhibitor and nonsteroidal anti-inflammatory drug (NSAID) use. The antihypertensive effect of ACE inhibitors may be diminished by NSAIDs. In persons who are elderly, volume-depleted, or with compromised renal function, coadministration of ACE inhibitors and NSAIDs may result in deterioration of renal function, including possible acute renal failure; these effects are usually reversible.
Fexofenadine; Pseudoephedrine: (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Finerenone: (Moderate) Monitor serum potassium concentrations closely if finerenone and angiotensin-converting enzyme inhibitors (ACEI) are used together. Concomitant use may increase the risk of hyperkalemia.
Fish Oil, Omega-3 Fatty Acids (Dietary Supplements): (Moderate) High doses of fish oil supplements may produce a blood pressure lowering effect. It is possible that additive reductions in blood pressure may be seen when fish oils are used in a patient already taking antihypertensive agents.
Fluorescein: (Moderate) Patients on angiotensin-converting enzyme inhibitors are at an increased risk of adverse reactions when administered fluorescein injection. If fluorescein injection is deemed necessary in a patient on ACE inhibitor therapy, monitor as appropriate during and after the procedure.
Flurbiprofen: (Moderate) Monitor blood pressure and renal function periodically during concomitant angiotensin-converting enzyme (ACE) inhibitor and nonsteroidal anti-inflammatory drug (NSAID) use. The antihypertensive effect of ACE inhibitors may be diminished by NSAIDs. In persons who are elderly, volume-depleted, or with compromised renal function, coadministration of ACE inhibitors and NSAIDs may result in deterioration of renal function, including possible acute renal failure; these effects are usually reversible.
Fosinopril; Hydrochlorothiazide, HCTZ: (Major) Discontinue the thiazide diuretic prior to starting captopril, if possible, or start captopril at the lower dose of 6.25 or 12.5 mg/day. Monitor blood pressure, particularly when doses are increased, and renal function during concomitant use. Concomitant use may increase the risk for hypotension or renal failure.
Furosemide: (Major) Discontinue the loop diuretic prior to starting captopril, if possible, or start captopril at the lower dose of 6.25 or 12.5 mg/day. Monitor blood pressure and renal function during concomitant use, particularly when doses are increased. Concomitant use may increase the risk for hypotension or renal failure.
General anesthetics: (Moderate) General anesthetics can potentiate the hypotensive effects of antihypertensive agents.
Glimepiride: (Moderate) Monitor blood glucose during concomitant sulfonylurea and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Glipizide: (Moderate) Monitor blood glucose during concomitant sulfonylurea and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Glipizide; Metformin: (Moderate) Monitor blood glucose during concomitant metformin and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia. (Moderate) Monitor blood glucose during concomitant sulfonylurea and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Glyburide: (Moderate) Monitor blood glucose during concomitant sulfonylurea and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Glyburide; Metformin: (Moderate) Monitor blood glucose during concomitant metformin and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia. (Moderate) Monitor blood glucose during concomitant sulfonylurea and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Gold: (Minor) Nitritoid reactions (facial flushing, diaphoresis, dizziness, nausea/vomiting, hypotension, tachycardia, syncope, and anaphylactic type reactions) or vasomotor reactions have been reported rarely in patients receiving injectable gold and concomitant ACE inhibitor therapy. Monitor closely for nitritoid reactions during co-therapy with gold and ACE inhibitor agents.
Guaifenesin; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Well-controlled hypertensive patients receiving phenylephrine at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure (especially systolic hypertension) has been reported in some patients.
Guaifenesin; Pseudoephedrine: (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Haloperidol: (Moderate) In general, haloperidol should be used cautiously with antihypertensive agents due to the possibility of additive hypotension.
Hydralazine; Isosorbide Dinitrate, ISDN: (Moderate) Concomitant use of nitrates with other antihypertensive agents can cause additive hypotensive effects. Dosage adjustments may be necessary.
Hydrochlorothiazide, HCTZ: (Major) Discontinue the thiazide diuretic prior to starting captopril, if possible, or start captopril at the lower dose of 6.25 or 12.5 mg/day. Monitor blood pressure, particularly when doses are increased, and renal function during concomitant use. Concomitant use may increase the risk for hypotension or renal failure.
Hydrochlorothiazide, HCTZ; Moexipril: (Major) Discontinue the thiazide diuretic prior to starting captopril, if possible, or start captopril at the lower dose of 6.25 or 12.5 mg/day. Monitor blood pressure, particularly when doses are increased, and renal function during concomitant use. Concomitant use may increase the risk for hypotension or renal failure.
Hydrocodone; Ibuprofen: (Moderate) Monitor blood pressure and renal function periodically during concomitant angiotensin-converting enzyme (ACE) inhibitor and nonsteroidal anti-inflammatory drug (NSAID) use. The antihypertensive effect of ACE inhibitors may be diminished by NSAIDs. In persons who are elderly, volume-depleted, or with compromised renal function, coadministration of ACE inhibitors and NSAIDs may result in deterioration of renal function, including possible acute renal failure; these effects are usually reversible.
Hyoscyamine; Methenamine; Methylene Blue; Phenyl Salicylate; Sodium Biphosphate: (Moderate) Aspirin, ASA may reduce the vasodilatory efficacy of ACE inhibitors by inhibiting the synthesis of vasodilatory prostaglandins. This interaction has been documented primarily in heart failure patients. However, the established benefits of using aspirin in combination with an ACE inhibitor in patients with ischemic heart disease and left ventricular dysfunction generally outweigh this concern. Patients receiving concurrent salicylates and ACE inhibitor therapy should be monitored for antihypertensive or vasodilatory efficacy; the dose of the ACE inhibitor can be adjusted if indicated based on clinical evaluation.
Ibritumomab Tiuxetan: (Major) Avoid coadministration of potassium phosphate and angiotensin-converting enzyme inhibitors as concurrent use may increase the risk of severe and potentially fatal hyperkalemia, particularly in high-risk patients (renal impairment, cardiac disease, adrenal insufficiency). If concomitant use is necessary, closely monitor serum potassium concentrations. (Moderate) Monitor serum potassium concentrations closely if potassium supplements and angiotensin-converting enzyme inhibitors (ACE inhibitors) are used together. Concomitant use may increase the risk of hyperkalemia.
Ibuprofen: (Moderate) Monitor blood pressure and renal function periodically during concomitant angiotensin-converting enzyme (ACE) inhibitor and nonsteroidal anti-inflammatory drug (NSAID) use. The antihypertensive effect of ACE inhibitors may be diminished by NSAIDs. In persons who are elderly, volume-depleted, or with compromised renal function, coadministration of ACE inhibitors and NSAIDs may result in deterioration of renal function, including possible acute renal failure; these effects are usually reversible.
Ibuprofen; Famotidine: (Moderate) Monitor blood pressure and renal function periodically during concomitant angiotensin-converting enzyme (ACE) inhibitor and nonsteroidal anti-inflammatory drug (NSAID) use. The antihypertensive effect of ACE inhibitors may be diminished by NSAIDs. In persons who are elderly, volume-depleted, or with compromised renal function, coadministration of ACE inhibitors and NSAIDs may result in deterioration of renal function, including possible acute renal failure; these effects are usually reversible.
Ibuprofen; Oxycodone: (Moderate) Monitor blood pressure and renal function periodically during concomitant angiotensin-converting enzyme (ACE) inhibitor and nonsteroidal anti-inflammatory drug (NSAID) use. The antihypertensive effect of ACE inhibitors may be diminished by NSAIDs. In persons who are elderly, volume-depleted, or with compromised renal function, coadministration of ACE inhibitors and NSAIDs may result in deterioration of renal function, including possible acute renal failure; these effects are usually reversible.
Ibuprofen; Pseudoephedrine: (Moderate) Monitor blood pressure and renal function periodically during concomitant angiotensin-converting enzyme (ACE) inhibitor and nonsteroidal anti-inflammatory drug (NSAID) use. The antihypertensive effect of ACE inhibitors may be diminished by NSAIDs. In persons who are elderly, volume-depleted, or with compromised renal function, coadministration of ACE inhibitors and NSAIDs may result in deterioration of renal function, including possible acute renal failure; these effects are usually reversible. (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Icatibant: (Minor) Although clinical data are lacking, icatibant is a bradykinin B2 receptor antagonist and may theoretically potentiate the antihypertensive effect of ACE inhibitors.
Iloperidone: (Moderate) Secondary to alpha-blockade, iloperidone can produce vasodilation that may result in additive effects during concurrent use with antihypertensive agents. The potential reduction in blood pressure can precipitate orthostatic hypotension and associated dizziness, tachycardia, and syncope. If concurrent use of iloperidone and antihypertensive agents is necessary, patients should be counseled on measures to prevent orthostatic hypotension, such as sitting on the edge of the bed for several minutes prior to standing in the morning and rising slowly from a seated position. Close monitoring of blood pressure is recommended until the full effects of the combination therapy are known.
Iloprost: (Moderate) Further reductions in blood pressure may occur when inhaled iloprost is administered to patients receiving other antihypertensive agents.
Incretin Mimetics: (Moderate) Monitor blood glucose during concomitant incretin mimetic and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Indapamide: (Moderate) The effects of indapamide may be additive when administered with other antihypertensive agents or diuretics. In some patients, this may be desirable, but orthostatic hypotension may occur. Patients with hyponatremia or hypovolemia are more susceptible to developing reversible renal insufficiency when given an angiotensin-converting enzyme inhibitors (ACE Inhibitors) and diuretic therapy concomitantly.
Indomethacin: (Moderate) Monitor blood pressure and renal function periodically during concomitant angiotensin-converting enzyme (ACE) inhibitor and nonsteroidal anti-inflammatory drug (NSAID) use. The antihypertensive effect of ACE inhibitors may be diminished by NSAIDs. In persons who are elderly, volume-depleted, or with compromised renal function, coadministration of ACE inhibitors and NSAIDs may result in deterioration of renal function, including possible acute renal failure; these effects are usually reversible.
Insulin Aspart: (Moderate) Monitor blood glucose during concomitant insulin and angiotensin-converting enzyme (ACE) inhibitor use; an insulin dose adjustment may be necessary. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Insulin Aspart; Insulin Aspart Protamine: (Moderate) Monitor blood glucose during concomitant insulin and angiotensin-converting enzyme (ACE) inhibitor use; an insulin dose adjustment may be necessary. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Insulin Degludec: (Moderate) Monitor blood glucose during concomitant insulin and angiotensin-converting enzyme (ACE) inhibitor use; an insulin dose adjustment may be necessary. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Insulin Degludec; Liraglutide: (Moderate) Monitor blood glucose during concomitant incretin mimetic and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia. (Moderate) Monitor blood glucose during concomitant insulin and angiotensin-converting enzyme (ACE) inhibitor use; an insulin dose adjustment may be necessary. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Insulin Detemir: (Moderate) Monitor blood glucose during concomitant insulin and angiotensin-converting enzyme (ACE) inhibitor use; an insulin dose adjustment may be necessary. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Insulin Glargine: (Moderate) Monitor blood glucose during concomitant insulin and angiotensin-converting enzyme (ACE) inhibitor use; an insulin dose adjustment may be necessary. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Insulin Glargine; Lixisenatide: (Moderate) Monitor blood glucose during concomitant incretin mimetic and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia. (Moderate) Monitor blood glucose during concomitant insulin and angiotensin-converting enzyme (ACE) inhibitor use; an insulin dose adjustment may be necessary. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Insulin Glulisine: (Moderate) Monitor blood glucose during concomitant insulin and angiotensin-converting enzyme (ACE) inhibitor use; an insulin dose adjustment may be necessary. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Insulin Lispro: (Moderate) Monitor blood glucose during concomitant insulin and angiotensin-converting enzyme (ACE) inhibitor use; an insulin dose adjustment may be necessary. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Insulin Lispro; Insulin Lispro Protamine: (Moderate) Monitor blood glucose during concomitant insulin and angiotensin-converting enzyme (ACE) inhibitor use; an insulin dose adjustment may be necessary. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Insulin, Inhaled: (Moderate) Monitor blood glucose during concomitant insulin and angiotensin-converting enzyme (ACE) inhibitor use; an insulin dose adjustment may be necessary. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Insulins: (Moderate) Monitor blood glucose during concomitant insulin and angiotensin-converting enzyme (ACE) inhibitor use; an insulin dose adjustment may be necessary. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Intravenous Lipid Emulsions: (Moderate) High doses of fish oil supplements may produce a blood pressure lowering effect. It is possible that additive reductions in blood pressure may be seen when fish oils are used in a patient already taking antihypertensive agents.
Iodine; Potassium Iodide, KI: (Moderate) Monitor serum potassium concentrations closely if potassium supplements and angiotensin-converting enzyme inhibitors (ACE inhibitors) are used together. Concomitant use may increase the risk of hyperkalemia.
Iodixanol: (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.
Iohexol: (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.
Iomeprol: (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.
Iopamidol: (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.
Iopromide: (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.
Ioversol: (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.
Irbesartan: (Major) In general, avoid combined use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) due to lack of benefit with concomitant use in most patients. Closely monitor blood pressure, renal function, and electrolytes in patients on ACE inhibitors and ARBs. Dual blockade of the renin-angiotensin system with ACE inhibitors and ARBs is associated with increased risks of hypotension, syncope, hyperkalemia, and changes in renal function, including acute renal failure, compared to monotherapy.
Irbesartan; Hydrochlorothiazide, HCTZ: (Major) Discontinue the thiazide diuretic prior to starting captopril, if possible, or start captopril at the lower dose of 6.25 or 12.5 mg/day. Monitor blood pressure, particularly when doses are increased, and renal function during concomitant use. Concomitant use may increase the risk for hypotension or renal failure. (Major) In general, avoid combined use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) due to lack of benefit with concomitant use in most patients. Closely monitor blood pressure, renal function, and electrolytes in patients on ACE inhibitors and ARBs. Dual blockade of the renin-angiotensin system with ACE inhibitors and ARBs is associated with increased risks of hypotension, syncope, hyperkalemia, and changes in renal function, including acute renal failure, compared to monotherapy.
Iron Dextran: (Moderate) The concomitant use of angiotensin-converting enzyme inhibitors (ACE inhibitors) with iron dextran may increase the risk for anaphylactic-type reactions. The factors that affect the risk for anaphylactic-type reactions to iron dextran products are not fully known but limited clinical data suggest the risk may be increased among patients with a history of drug allergy or multiple drug allergies. Patients should be monitored for signs and symptoms of anaphylactic-type reactions during all iron dextran administrations.
Isocarboxazid: (Moderate) Additive hypotensive effects may be seen when monoamine oxidase inhibitors (MAOIs) are combined with antihypertensives. Careful monitoring of blood pressure is suggested during concurrent therapy of MAOIs with angiotensin-converting enzyme inhibitors (ACE inhibitors). Patients should be instructed to rise slowly from a sitting position, and to report syncope or changes in blood pressure or heart rate to their health care provider.
Isoflurane: (Moderate) General anesthetics can potentiate the hypotensive effects of antihypertensive agents.
Isophane Insulin (NPH): (Moderate) Monitor blood glucose during concomitant insulin and angiotensin-converting enzyme (ACE) inhibitor use; an insulin dose adjustment may be necessary. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Isoproterenol: (Moderate) The pharmacologic effects of isoproterenol may cause an increase in blood pressure. If isoproterenol is used concomitantly with antihypertensives, the blood pressure should be monitored as the administration of isoproterenol can compromise the effectiveness of antihypertensive agents.
Isosorbide Dinitrate, ISDN: (Moderate) Concomitant use of nitrates with other antihypertensive agents can cause additive hypotensive effects. Dosage adjustments may be necessary.
Isosorbide Mononitrate: (Moderate) Concomitant use of nitrates with other antihypertensive agents can cause additive hypotensive effects. Dosage adjustments may be necessary.
Isosulfan Blue: (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.
Ketamine: (Moderate) General anesthetics can potentiate the hypotensive effects of antihypertensive agents.
Ketoprofen: (Moderate) Monitor blood pressure and renal function periodically during concomitant angiotensin-converting enzyme (ACE) inhibitor and nonsteroidal anti-inflammatory drug (NSAID) use. The antihypertensive effect of ACE inhibitors may be diminished by NSAIDs. In persons who are elderly, volume-depleted, or with compromised renal function, coadministration of ACE inhibitors and NSAIDs may result in deterioration of renal function, including possible acute renal failure; these effects are usually reversible.
Ketorolac: (Moderate) Monitor blood pressure and renal function periodically during concomitant angiotensin-converting enzyme (ACE) inhibitor and nonsteroidal anti-inflammatory drug (NSAID) use. The antihypertensive effect of ACE inhibitors may be diminished by NSAIDs. In persons who are elderly, volume-depleted, or with compromised renal function, coadministration of ACE inhibitors and NSAIDs may result in deterioration of renal function, including possible acute renal failure; these effects are usually reversible.
Lanthanum Carbonate: (Moderate) ACE Inhibitors should not be taken within 2 hours of dosing with lanthanum carbonate. Oral compounds known to interact with cationic antacids may similarly be bound with lanthanum carbonate and have their absorption reduced. If these agents are used concomitantly, separate the dosing intervals appropriately. Monitor the clinical condition of the patient to ensure the proper clinical response to the ACE inhibitor is obtained.
Levodopa: (Moderate) Concomitant use of antihypertensive agents with levodopa can result in additive hypotensive effects.
Lidocaine; Epinephrine: (Moderate) Antihypertensives, including angiotensin-converting enzyme inhibitors, antagonize the vasopressor effects of parenteral epinephrine.
Linagliptin; Metformin: (Moderate) Monitor blood glucose during concomitant metformin and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Liraglutide: (Moderate) Monitor blood glucose during concomitant incretin mimetic and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Lisdexamfetamine: (Minor) Lisdexamfetamine may increase both systolic and diastolic blood pressure and may counteract the activity of some antihypertensive agents, like angiotensin-converting enzyme inhibitors (ACE inhibitors). Close monitoring of blood pressure is advised.
Lisinopril; Hydrochlorothiazide, HCTZ: (Major) Discontinue the thiazide diuretic prior to starting captopril, if possible, or start captopril at the lower dose of 6.25 or 12.5 mg/day. Monitor blood pressure, particularly when doses are increased, and renal function during concomitant use. Concomitant use may increase the risk for hypotension or renal failure.
Lithium: (Moderate) Monitor serum lithium concentrations during concomitant angiotensin-converting enzyme inhibitor use; reduce the lithium dose based on serum lithium concentration and clinical response. Concomitant use may increase steady-state lithium concentrations.
Lixisenatide: (Moderate) Monitor blood glucose during concomitant incretin mimetic and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Loop diuretics: (Major) Discontinue the loop diuretic prior to starting captopril, if possible, or start captopril at the lower dose of 6.25 or 12.5 mg/day. Monitor blood pressure and renal function during concomitant use, particularly when doses are increased. Concomitant use may increase the risk for hypotension or renal failure.
Loratadine; Pseudoephedrine: (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Losartan: (Major) In general, avoid combined use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) due to lack of benefit with concomitant use in most patients. Closely monitor blood pressure, renal function, and electrolytes in patients on ACE inhibitors and ARBs. Dual blockade of the renin-angiotensin system with ACE inhibitors and ARBs is associated with increased risks of hypotension, syncope, hyperkalemia, and changes in renal function, including acute renal failure, compared to monotherapy.
Losartan; Hydrochlorothiazide, HCTZ: (Major) Discontinue the thiazide diuretic prior to starting captopril, if possible, or start captopril at the lower dose of 6.25 or 12.5 mg/day. Monitor blood pressure, particularly when doses are increased, and renal function during concomitant use. Concomitant use may increase the risk for hypotension or renal failure. (Major) In general, avoid combined use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) due to lack of benefit with concomitant use in most patients. Closely monitor blood pressure, renal function, and electrolytes in patients on ACE inhibitors and ARBs. Dual blockade of the renin-angiotensin system with ACE inhibitors and ARBs is associated with increased risks of hypotension, syncope, hyperkalemia, and changes in renal function, including acute renal failure, compared to monotherapy.
Lurasidone: (Moderate) Due to the antagonism of lurasidone at alpha-1 adrenergic receptors, the drug may enhance the hypotensive effects of alpha-blockers and other antihypertensive agents. If concurrent use of lurasidone and antihypertensive agents is necessary, patients should be counseled on measures to prevent orthostatic hypotension, such as sitting on the edge of the bed for several minutes prior to standing in the morning and rising slowly from a seated position. Close monitoring of blood pressure is recommended until the full effects of the combination therapy are known.
Magnesium Hydroxide: (Major) Antacids can decrease the GI absorption of captopril if administered simultaneously.
Magnesium Salicylate: (Moderate) Aspirin, ASA may reduce the vasodilatory efficacy of ACE inhibitors by inhibiting the synthesis of vasodilatory prostaglandins. This interaction has been documented primarily in heart failure patients. However, the established benefits of using aspirin in combination with an ACE inhibitor in patients with ischemic heart disease and left ventricular dysfunction generally outweigh this concern. Patients receiving concurrent salicylates and ACE inhibitor therapy should be monitored for antihypertensive or vasodilatory efficacy; the dose of the ACE inhibitor can be adjusted if indicated based on clinical evaluation.
Magnesium Salts: (Major) Antacids can decrease the GI absorption of captopril if administered simultaneously. (Moderate) Use caution when prescribing sulfate salt bowel preparation in patients taking concomitant medications that may affect renal function such as angiotensin-converting enzyme inhibitors (ACE inhibitors).
Magnesium Sulfate; Potassium Sulfate; Sodium Sulfate: (Moderate) Monitor renal function during concomitant angiotensin-converting enzyme inhibitor and magnesium sulfate; potassium sulfate; sodium sulfate bowel preparation due to risk for renal injury; ensure adequate hydration.
Meclofenamate Sodium: (Moderate) Monitor blood pressure and renal function periodically during concomitant angiotensin-converting enzyme (ACE) inhibitor and nonsteroidal anti-inflammatory drug (NSAID) use. The antihypertensive effect of ACE inhibitors may be diminished by NSAIDs. In persons who are elderly, volume-depleted, or with compromised renal function, coadministration of ACE inhibitors and NSAIDs may result in deterioration of renal function, including possible acute renal failure; these effects are usually reversible.
Mefenamic Acid: (Moderate) Monitor blood pressure and renal function periodically during concomitant angiotensin-converting enzyme (ACE) inhibitor and nonsteroidal anti-inflammatory drug (NSAID) use. The antihypertensive effect of ACE inhibitors may be diminished by NSAIDs. In persons who are elderly, volume-depleted, or with compromised renal function, coadministration of ACE inhibitors and NSAIDs may result in deterioration of renal function, including possible acute renal failure; these effects are usually reversible.
Meglitinides: (Moderate) ACE inhibitors may enhance the hypoglycemic effects of insulin or other antidiabetic agents by improving insulin sensitivity. Patients receiving antidiabetic agents can become hypoglycemic if ACE inhibitors are administered concomitantly. Patients receiving these drugs concomitantly with antidiabetic agents should be monitored for changes in glycemic control.
Meloxicam: (Moderate) Monitor blood pressure and renal function periodically during concomitant angiotensin-converting enzyme (ACE) inhibitor and nonsteroidal anti-inflammatory drug (NSAID) use. The antihypertensive effect of ACE inhibitors may be diminished by NSAIDs. In persons who are elderly, volume-depleted, or with compromised renal function, coadministration of ACE inhibitors and NSAIDs may result in deterioration of renal function, including possible acute renal failure; these effects are usually reversible.
Metformin: (Moderate) Monitor blood glucose during concomitant metformin and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Metformin; Repaglinide: (Moderate) ACE inhibitors may enhance the hypoglycemic effects of insulin or other antidiabetic agents by improving insulin sensitivity. Patients receiving antidiabetic agents can become hypoglycemic if ACE inhibitors are administered concomitantly. Patients receiving these drugs concomitantly with antidiabetic agents should be monitored for changes in glycemic control. (Moderate) Monitor blood glucose during concomitant metformin and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Metformin; Saxagliptin: (Moderate) Monitor blood glucose during concomitant metformin and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Metformin; Sitagliptin: (Moderate) Monitor blood glucose during concomitant metformin and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Methamphetamine: (Minor) Amphetamines increase both systolic and diastolic blood pressure and may counteract the activity of some antihypertensive agents, like angiotensin-converting enzyme inhibitors (ACE inhibitors). Close monitoring of blood pressure is advised.
Methenamine; Sodium Salicylate: (Moderate) Aspirin, ASA may reduce the vasodilatory efficacy of ACE inhibitors by inhibiting the synthesis of vasodilatory prostaglandins. This interaction has been documented primarily in heart failure patients. However, the established benefits of using aspirin in combination with an ACE inhibitor in patients with ischemic heart disease and left ventricular dysfunction generally outweigh this concern. Patients receiving concurrent salicylates and ACE inhibitor therapy should be monitored for antihypertensive or vasodilatory efficacy; the dose of the ACE inhibitor can be adjusted if indicated based on clinical evaluation.
Methohexital: (Moderate) Concurrent use of methohexital and antihypertensive agents increases the risk of developing hypotension.
Methylphenidate Derivatives: (Moderate) Periodic evaluation of blood pressure is advisable during concurrent use of methylphenidate derivatives and antihypertensive agents, particularly during initial coadministration and after dosage increases of methylphenidate derivatives. Methylphenidate derivatives can reduce the hypotensive effect of antihypertensive agents such as angiotensin-converting enzyme inhibitors.
Methylphenidate: (Moderate) Periodic evaluation of blood pressure is advisable during concurrent use of methylphenidate derivatives and antihypertensive agents, particularly during initial coadministration and after dosage increases of methylphenidate derivatives. Methylphenidate derivatives can reduce the hypotensive effect of antihypertensive agents such as angiotensin-converting enzyme inhibitors.
Metolazone: (Major) Discontinue the thiazide diuretic prior to starting captopril, if possible, or start captopril at the lower dose of 6.25 or 12.5 mg/day. Monitor blood pressure, particularly when doses are increased, and renal function during concomitant use. Concomitant use may increase the risk for hypotension or renal failure.
Metoprolol; Hydrochlorothiazide, HCTZ: (Major) Discontinue the thiazide diuretic prior to starting captopril, if possible, or start captopril at the lower dose of 6.25 or 12.5 mg/day. Monitor blood pressure, particularly when doses are increased, and renal function during concomitant use. Concomitant use may increase the risk for hypotension or renal failure.
Miglitol: (Moderate) ACE inhibitors may enhance the hypoglycemic effects of insulin or other antidiabetic agents by improving insulin sensitivity. Patients receiving antidiabetic agents can become hypoglycemic if ACE inhibitors are administered concomitantly. Patients receiving these drugs concomitantly with antidiabetic agents should be monitored for changes in glycemic control.
Milrinone: (Moderate) Concurrent administration of antihypertensive agents could lead to additive hypotension when administered with milrinone. Titrate milrinone dosage according to hemodynamic response.
Nabumetone: (Moderate) Monitor blood pressure and renal function periodically during concomitant angiotensin-converting enzyme (ACE) inhibitor and nonsteroidal anti-inflammatory drug (NSAID) use. The antihypertensive effect of ACE inhibitors may be diminished by NSAIDs. In persons who are elderly, volume-depleted, or with compromised renal function, coadministration of ACE inhibitors and NSAIDs may result in deterioration of renal function, including possible acute renal failure; these effects are usually reversible.
Nanoparticle Albumin-Bound Sirolimus: (Moderate) Sirolimus has been associated with the development of angioedema. The use of sirolimus with other drugs known to cause angioedema, such as angiotensin-converting enzyme inhibitors may increase the risk of developing angioedema. Patients should be monitored for angioedema if any of these drugs are coadministered with sirolimus.
Naproxen: (Moderate) Monitor blood pressure and renal function periodically during concomitant angiotensin-converting enzyme (ACE) inhibitor and nonsteroidal anti-inflammatory drug (NSAID) use. The antihypertensive effect of ACE inhibitors may be diminished by NSAIDs. In persons who are elderly, volume-depleted, or with compromised renal function, coadministration of ACE inhibitors and NSAIDs may result in deterioration of renal function, including possible acute renal failure; these effects are usually reversible.
Naproxen; Esomeprazole: (Moderate) Monitor blood pressure and renal function periodically during concomitant angiotensin-converting enzyme (ACE) inhibitor and nonsteroidal anti-inflammatory drug (NSAID) use. The antihypertensive effect of ACE inhibitors may be diminished by NSAIDs. In persons who are elderly, volume-depleted, or with compromised renal function, coadministration of ACE inhibitors and NSAIDs may result in deterioration of renal function, including possible acute renal failure; these effects are usually reversible.
Naproxen; Pseudoephedrine: (Moderate) Monitor blood pressure and renal function periodically during concomitant angiotensin-converting enzyme (ACE) inhibitor and nonsteroidal anti-inflammatory drug (NSAID) use. The antihypertensive effect of ACE inhibitors may be diminished by NSAIDs. In persons who are elderly, volume-depleted, or with compromised renal function, coadministration of ACE inhibitors and NSAIDs may result in deterioration of renal function, including possible acute renal failure; these effects are usually reversible. (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Nateglinide: (Moderate) ACE inhibitors may enhance the hypoglycemic effects of insulin or other antidiabetic agents by improving insulin sensitivity. Patients receiving antidiabetic agents can become hypoglycemic if ACE inhibitors are administered concomitantly. Patients receiving these drugs concomitantly with antidiabetic agents should be monitored for changes in glycemic control.
Nebivolol; Valsartan: (Major) In general, avoid combined use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) due to lack of benefit with concomitant use in most patients. Closely monitor blood pressure, renal function, and electrolytes in patients on ACE inhibitors and ARBs. Dual blockade of the renin-angiotensin system with ACE inhibitors and ARBs is associated with increased risks of hypotension, syncope, hyperkalemia, and changes in renal function, including acute renal failure, compared to monotherapy.
Nefazodone: (Minor) Although relatively infrequent, nefazodone may cause orthostatic hypotension in some patients; this effect may be additive with antihypertensive agents. Blood pressure monitoring and dosage adjustments of either drug may be necessary.
Nesiritide, BNP: (Major) The potential for hypotension may be increased when coadministering nesiritide with antihypertensive agents.
Niacin, Niacinamide: (Moderate) Cutaneous vasodilation induced by niacin may become problematic if high-dose niacin is used concomitantly with other antihypertensive agents. This effect is of particular concern in the setting of acute myocardial infarction, unstable angina, or other acute hemodynamic compromise.
Nitrates: (Moderate) Concomitant use of nitrates with other antihypertensive agents can cause additive hypotensive effects. Dosage adjustments may be necessary.
Nitroglycerin: (Moderate) Concomitant use of nitrates with other antihypertensive agents can cause additive hypotensive effects. Dosage adjustments may be necessary.
Nitroprusside: (Moderate) Additive hypotensive effects may occur when nitroprusside is used concomitantly with other antihypertensive agents. Dosages should be adjusted carefully, according to blood pressure.
Non-Ionic Contrast Media: (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.
Nonsteroidal antiinflammatory drugs: (Moderate) Monitor blood pressure and renal function periodically during concomitant angiotensin-converting enzyme (ACE) inhibitor and nonsteroidal anti-inflammatory drug (NSAID) use. The antihypertensive effect of ACE inhibitors may be diminished by NSAIDs. In persons who are elderly, volume-depleted, or with compromised renal function, coadministration of ACE inhibitors and NSAIDs may result in deterioration of renal function, including possible acute renal failure; these effects are usually reversible.
Olanzapine: (Moderate) Olanzapine may induce orthostatic hypotension and thus enhance the effects of antihypertensive agents.
Olanzapine; Fluoxetine: (Moderate) Olanzapine may induce orthostatic hypotension and thus enhance the effects of antihypertensive agents.
Olanzapine; Samidorphan: (Moderate) Olanzapine may induce orthostatic hypotension and thus enhance the effects of antihypertensive agents.
Olmesartan: (Major) In general, avoid combined use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) due to lack of benefit with concomitant use in most patients. Closely monitor blood pressure, renal function, and electrolytes in patients on ACE inhibitors and ARBs. Dual blockade of the renin-angiotensin system with ACE inhibitors and ARBs is associated with increased risks of hypotension, syncope, hyperkalemia, and changes in renal function, including acute renal failure, compared to monotherapy.
Olmesartan; Amlodipine; Hydrochlorothiazide, HCTZ: (Major) Discontinue the thiazide diuretic prior to starting captopril, if possible, or start captopril at the lower dose of 6.25 or 12.5 mg/day. Monitor blood pressure, particularly when doses are increased, and renal function during concomitant use. Concomitant use may increase the risk for hypotension or renal failure. (Major) In general, avoid combined use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) due to lack of benefit with concomitant use in most patients. Closely monitor blood pressure, renal function, and electrolytes in patients on ACE inhibitors and ARBs. Dual blockade of the renin-angiotensin system with ACE inhibitors and ARBs is associated with increased risks of hypotension, syncope, hyperkalemia, and changes in renal function, including acute renal failure, compared to monotherapy.
Olmesartan; Hydrochlorothiazide, HCTZ: (Major) Discontinue the thiazide diuretic prior to starting captopril, if possible, or start captopril at the lower dose of 6.25 or 12.5 mg/day. Monitor blood pressure, particularly when doses are increased, and renal function during concomitant use. Concomitant use may increase the risk for hypotension or renal failure. (Major) In general, avoid combined use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) due to lack of benefit with concomitant use in most patients. Closely monitor blood pressure, renal function, and electrolytes in patients on ACE inhibitors and ARBs. Dual blockade of the renin-angiotensin system with ACE inhibitors and ARBs is associated with increased risks of hypotension, syncope, hyperkalemia, and changes in renal function, including acute renal failure, compared to monotherapy.
Oxaprozin: (Moderate) Monitor blood pressure and renal function periodically during concomitant angiotensin-converting enzyme (ACE) inhibitor and nonsteroidal anti-inflammatory drug (NSAID) use. The antihypertensive effect of ACE inhibitors may be diminished by NSAIDs. In persons who are elderly, volume-depleted, or with compromised renal function, coadministration of ACE inhibitors and NSAIDs may result in deterioration of renal function, including possible acute renal failure; these effects are usually reversible.
Oxymetazoline: (Major) The vasoconstricting actions of oxymetazoline, an alpha adrenergic agonist, may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. If these drugs are used together, closely monitor for changes in blood pressure.
Paliperidone: (Moderate) Paliperidone may cause orthostatic hypotension, thereby enhancing the hypotensive effects of antihypertensive agents. Orthostatic vital signs should be monitored in patients receiving paliperidone and angiotensin-converting enzyme inhibitors who are susceptible to hypotension.
Pentoxifylline: (Moderate) Pentoxifylline has been used concurrently with antihypertensive drugs (beta blockers, diuretics) without observed problems. Small decreases in blood pressure have been observed in some patients treated with pentoxifylline; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensives. If indicated, dosage of the antihypertensive agents should be reduced.
Phenelzine: (Moderate) Additive hypotensive effects may be seen when monoamine oxidase inhibitors (MAOIs) are combined with antihypertensives. Careful monitoring of blood pressure is suggested during concurrent therapy of MAOIs with angiotensin-converting enzyme inhibitors (ACE inhibitors). Patients should be instructed to rise slowly from a sitting position, and to report syncope or changes in blood pressure or heart rate to their health care provider.
Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Well-controlled hypertensive patients receiving phenylephrine at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure (especially systolic hypertension) has been reported in some patients.
Pioglitazone: (Moderate) Monitor blood glucose during concomitant thiazolidinedione and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Pioglitazone; Glimepiride: (Moderate) Monitor blood glucose during concomitant sulfonylurea and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia. (Moderate) Monitor blood glucose during concomitant thiazolidinedione and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Pioglitazone; Metformin: (Moderate) Monitor blood glucose during concomitant metformin and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia. (Moderate) Monitor blood glucose during concomitant thiazolidinedione and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Piroxicam: (Moderate) Monitor blood pressure and renal function periodically during concomitant angiotensin-converting enzyme (ACE) inhibitor and nonsteroidal anti-inflammatory drug (NSAID) use. The antihypertensive effect of ACE inhibitors may be diminished by NSAIDs. In persons who are elderly, volume-depleted, or with compromised renal function, coadministration of ACE inhibitors and NSAIDs may result in deterioration of renal function, including possible acute renal failure; these effects are usually reversible.
Polyethylene Glycol; Electrolytes: (Moderate) Monitor renal function during concomitant angiotensin-converting enzyme inhibitor and magnesium sulfate; potassium sulfate; sodium sulfate bowel preparation due to risk for renal injury; ensure adequate hydration.
Polyethylene Glycol; Electrolytes; Ascorbic Acid: (Moderate) Monitor renal function during concomitant angiotensin-converting enzyme inhibitor and magnesium sulfate; potassium sulfate; sodium sulfate bowel preparation due to risk for renal injury; ensure adequate hydration.
Potassium Acetate: (Moderate) Monitor serum potassium concentrations closely if potassium supplements and angiotensin-converting enzyme inhibitors (ACE inhibitors) are used together. Concomitant use may increase the risk of hyperkalemia.
Potassium Bicarbonate: (Moderate) Monitor serum potassium concentrations closely if potassium supplements and angiotensin-converting enzyme inhibitors (ACE inhibitors) are used together. Concomitant use may increase the risk of hyperkalemia.
Potassium Chloride: (Moderate) Monitor serum potassium concentrations closely if potassium supplements and angiotensin-converting enzyme inhibitors (ACE inhibitors) are used together. Concomitant use may increase the risk of hyperkalemia.
Potassium Citrate: (Moderate) Monitor serum potassium concentrations closely if potassium supplements and angiotensin-converting enzyme inhibitors (ACE inhibitors) are used together. Concomitant use may increase the risk of hyperkalemia.
Potassium Citrate; Citric Acid: (Moderate) Monitor serum potassium concentrations closely if potassium supplements and angiotensin-converting enzyme inhibitors (ACE inhibitors) are used together. Concomitant use may increase the risk of hyperkalemia.
Potassium Gluconate: (Moderate) Monitor serum potassium concentrations closely if potassium supplements and angiotensin-converting enzyme inhibitors (ACE inhibitors) are used together. Concomitant use may increase the risk of hyperkalemia.
Potassium Iodide, KI: (Moderate) Monitor serum potassium concentrations closely if potassium supplements and angiotensin-converting enzyme inhibitors (ACE inhibitors) are used together. Concomitant use may increase the risk of hyperkalemia.
Potassium Phosphate: (Major) Avoid coadministration of potassium phosphate and angiotensin-converting enzyme inhibitors as concurrent use may increase the risk of severe and potentially fatal hyperkalemia, particularly in high-risk patients (renal impairment, cardiac disease, adrenal insufficiency). If concomitant use is necessary, closely monitor serum potassium concentrations.
Potassium Phosphate; Sodium Phosphate: (Major) Avoid coadministration of potassium phosphate and angiotensin-converting enzyme inhibitors as concurrent use may increase the risk of severe and potentially fatal hyperkalemia, particularly in high-risk patients (renal impairment, cardiac disease, adrenal insufficiency). If concomitant use is necessary, closely monitor serum potassium concentrations.
Potassium: (Moderate) Monitor serum potassium concentrations closely if potassium supplements and angiotensin-converting enzyme inhibitors (ACE inhibitors) are used together. Concomitant use may increase the risk of hyperkalemia.
Pramlintide: (Moderate) ACE inhibitors may enhance the hypoglycemic effects of antidiabetic agents by improving insulin sensitivity. Patients receiving these drugs concomitantly with antidiabetic agents should be monitored for changes in glycemic control.
Prazosin: (Moderate) Prazosin is well-known to produce a 'first-dose' phenomenon. Some patients develop significant hypotension shortly after administration of the first dose. The first dose response (acute postural hypotension) of prazosin may be exaggerated in patients who are receiving beta-adrenergic blockers, diuretics, or other antihypertensive agents. Concomitant administration of prazosin with other antihypertensive agents is not prohibited, however. This can be therapeutically advantageous, but lower dosages of each agent should be used.
Pregabalin: (Moderate) Monitor for signs and symptoms of angioedema during concomitant angiotensin-converting enzyme inhibitor and pregabalin use. Concomitant use may increase the risk of developing angioedema.
Prilocaine; Epinephrine: (Moderate) Antihypertensives, including angiotensin-converting enzyme inhibitors, antagonize the vasopressor effects of parenteral epinephrine.
Probenecid: (Moderate) Probenecid decreases the renal tubular secretion of captopril, resulting in higher captopril serum concentrations. If probenecid is given to a patient stabilized on captopril, hypotension may occur. This interaction would appear to be of lesser significance if captopril is added after probenecid therapy is in place.
Probenecid; Colchicine: (Moderate) Probenecid decreases the renal tubular secretion of captopril, resulting in higher captopril serum concentrations. If probenecid is given to a patient stabilized on captopril, hypotension may occur. This interaction would appear to be of lesser significance if captopril is added after probenecid therapy is in place.
Procainamide: (Moderate) Procainamide can decrease blood pressure and should be used cautiously in patients receiving antihypertensive agents. Intravenous administration of procainamide is more likely to cause hypotensive effects.
Promethazine; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Well-controlled hypertensive patients receiving phenylephrine at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure (especially systolic hypertension) has been reported in some patients.
Propofol: (Moderate) General anesthetics can potentiate the hypotensive effects of antihypertensive agents.
Pseudoephedrine: (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Pseudoephedrine; Triprolidine: (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Quinapril; Hydrochlorothiazide, HCTZ: (Major) Discontinue the thiazide diuretic prior to starting captopril, if possible, or start captopril at the lower dose of 6.25 or 12.5 mg/day. Monitor blood pressure, particularly when doses are increased, and renal function during concomitant use. Concomitant use may increase the risk for hypotension or renal failure.
Quinidine: (Moderate) Quinidine can decrease blood pressure and should be used cautiously in patients receiving antihypertensive agents due to the potential for additive hypotension.
Rasagiline: (Moderate) Additive hypotensive effects may be seen when monoamine oxidase inhibitors (MAOIs) are combined with antihypertensives. Careful monitoring of blood pressure is suggested during concurrent therapy of MAOIs with angiotensin-converting enzyme inhibitors (ACE inhibitors). Patients should be instructed to rise slowly from a sitting position, and to report syncope or changes in blood pressure or heart rate to their health care provider.
Regular Insulin: (Moderate) Monitor blood glucose during concomitant insulin and angiotensin-converting enzyme (ACE) inhibitor use; an insulin dose adjustment may be necessary. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Regular Insulin; Isophane Insulin (NPH): (Moderate) Monitor blood glucose during concomitant insulin and angiotensin-converting enzyme (ACE) inhibitor use; an insulin dose adjustment may be necessary. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Repaglinide: (Moderate) ACE inhibitors may enhance the hypoglycemic effects of insulin or other antidiabetic agents by improving insulin sensitivity. Patients receiving antidiabetic agents can become hypoglycemic if ACE inhibitors are administered concomitantly. Patients receiving these drugs concomitantly with antidiabetic agents should be monitored for changes in glycemic control.
Risperidone: (Moderate) Risperidone may induce orthostatic hypotension and thus enhance the hypotensive effects of antihypertensive agents. Lower initial doses or slower dose titration of risperidone may be necessary in patients receiving antihypertensive agents concomitantly.
Rosiglitazone: (Moderate) Monitor blood glucose during concomitant thiazolidinedione and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Sacubitril; Valsartan: (Contraindicated) Sacubitril; valsartan is contraindicated with the concomitant use of angiotensin-converting enzyme inhibitors (ACE inhibitors) due to the increased risk of angioedema. Do not administer sacubitril; valsartan within 36 hours of switching to or from an ACE inhibitor. (Major) In general, avoid combined use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) due to lack of benefit with concomitant use in most patients. Closely monitor blood pressure, renal function, and electrolytes in patients on ACE inhibitors and ARBs. Dual blockade of the renin-angiotensin system with ACE inhibitors and ARBs is associated with increased risks of hypotension, syncope, hyperkalemia, and changes in renal function, including acute renal failure, compared to monotherapy.
Salicylates: (Moderate) Aspirin, ASA may reduce the vasodilatory efficacy of ACE inhibitors by inhibiting the synthesis of vasodilatory prostaglandins. This interaction has been documented primarily in heart failure patients. However, the established benefits of using aspirin in combination with an ACE inhibitor in patients with ischemic heart disease and left ventricular dysfunction generally outweigh this concern. Patients receiving concurrent salicylates and ACE inhibitor therapy should be monitored for antihypertensive or vasodilatory efficacy; the dose of the ACE inhibitor can be adjusted if indicated based on clinical evaluation.
Salsalate: (Moderate) Aspirin, ASA may reduce the vasodilatory efficacy of ACE inhibitors by inhibiting the synthesis of vasodilatory prostaglandins. This interaction has been documented primarily in heart failure patients. However, the established benefits of using aspirin in combination with an ACE inhibitor in patients with ischemic heart disease and left ventricular dysfunction generally outweigh this concern. Patients receiving concurrent salicylates and ACE inhibitor therapy should be monitored for antihypertensive or vasodilatory efficacy; the dose of the ACE inhibitor can be adjusted if indicated based on clinical evaluation.
Semaglutide: (Moderate) Monitor blood glucose during concomitant incretin mimetic and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Serdexmethylphenidate; Dexmethylphenidate: (Moderate) Periodic evaluation of blood pressure is advisable during concurrent use of methylphenidate derivatives and antihypertensive agents, particularly during initial coadministration and after dosage increases of methylphenidate derivatives. Methylphenidate derivatives can reduce the hypotensive effect of antihypertensive agents such as angiotensin-converting enzyme inhibitors.
Sevoflurane: (Moderate) General anesthetics can potentiate the hypotensive effects of antihypertensive agents.
SGLT2 Inhibitors: (Moderate) Monitor blood glucose during concomitant SGLT2 inhibitor and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Silodosin: (Moderate) During clinical trials with silodosin, the incidence of dizziness and orthostatic hypotension was higher in patients receiving concomitant antihypertensive treatment. Thus, caution is advisable when silodosin is administered with antihypertensive agents.
Sirolimus: (Moderate) Sirolimus has been associated with the development of angioedema. The use of sirolimus with other drugs known to cause angioedema, such as angiotensin-converting enzyme inhibitors may increase the risk of developing angioedema. Patients should be monitored for angioedema if any of these drugs are coadministered with sirolimus.
Sodium Phosphate Monobasic Monohydrate; Sodium Phosphate Dibasic Anhydrous: (Moderate) Concomitant use of medicines with potential to alter renal perfusion or function such as angiotensin-converting enzyme inhibitors, may increase the risk of acute phosphate nephropathy in patients taking sodium phosphate monobasic monohydrate; sodium phosphate dibasic anhydrous.
Sodium picosulfate; Magnesium oxide; Anhydrous citric acid: (Moderate) Use caution when prescribing sodium picosulfate; magnesium oxide; anhydrous citric acid in patients taking concomitant medications that may affect renal function such as angiotensin-converting enzyme inhibitors (ACE inhibitors). In addition, use caution in patients receiving drugs where hypokalemia is a particular risk.
Sodium Sulfate; Magnesium Sulfate; Potassium Chloride: (Moderate) Monitor serum potassium concentrations closely if potassium supplements and angiotensin-converting enzyme inhibitors (ACE inhibitors) are used together. Concomitant use may increase the risk of hyperkalemia. (Moderate) Use caution when prescribing sulfate salt bowel preparation in patients taking concomitant medications that may affect renal function such as angiotensin-converting enzyme inhibitors (ACE inhibitors).
Sotagliflozin: (Moderate) Monitor blood glucose during concomitant SGLT2 inhibitor and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Sparsentan: (Major) Hold angiotensin-converting enzyme inhibitor therapy when initiating sparsentan and until a stable dose of sparsentan is achieved. Frequently monitor potassium during concomitant use due to the increased risk for hyperkalemia.
Spironolactone: (Moderate) Monitor serum potassium concentrations closely if ACE inhibitors and spironolactone are used together. Concomitant use may increase the risk of hyperkalemia, especially in elderly patients or patients with impaired renal function.
Spironolactone; Hydrochlorothiazide, HCTZ: (Major) Discontinue the thiazide diuretic prior to starting captopril, if possible, or start captopril at the lower dose of 6.25 or 12.5 mg/day. Monitor blood pressure, particularly when doses are increased, and renal function during concomitant use. Concomitant use may increase the risk for hypotension or renal failure. (Moderate) Monitor serum potassium concentrations closely if ACE inhibitors and spironolactone are used together. Concomitant use may increase the risk of hyperkalemia, especially in elderly patients or patients with impaired renal function.
Sulfacetamide; Sulfur: (Moderate) Cutaneous vasodilation induced by niacin may become problematic if high-dose niacin is used concomitantly with other antihypertensive agents.
Sulfamethoxazole; Trimethoprim, SMX-TMP, Cotrimoxazole: (Moderate) Monitor for hyperkalemia if concomitant use of an angiotensin-converting enzyme (ACE) inhibitor and trimethoprim is necessary. Avoid concomitant use and consider alternative antibiotic therapy in patients with additional risk factors for hyperkalemia, including patients older than 65 years, those with underlying disorders of potassium metabolism, renal insufficiency, or those requiring high doses of trimethoprim. Amongst patients older than 65 years, concomitant use has been associated with a 2- to 7-fold increased risk of significant hyperkalemia compared to other antibiotics. Trimethoprim has a potassium-sparing effect on the distal nephron and may induce hyperkalemia, especially in those with pre-existing risk factors.
Sulfonylureas: (Moderate) Monitor blood glucose during concomitant sulfonylurea and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Sulindac: (Moderate) Monitor blood pressure and renal function periodically during concomitant angiotensin-converting enzyme (ACE) inhibitor and nonsteroidal anti-inflammatory drug (NSAID) use. The antihypertensive effect of ACE inhibitors may be diminished by NSAIDs. In persons who are elderly, volume-depleted, or with compromised renal function, coadministration of ACE inhibitors and NSAIDs may result in deterioration of renal function, including possible acute renal failure; these effects are usually reversible.
Sumatriptan; Naproxen: (Moderate) Monitor blood pressure and renal function periodically during concomitant angiotensin-converting enzyme (ACE) inhibitor and nonsteroidal anti-inflammatory drug (NSAID) use. The antihypertensive effect of ACE inhibitors may be diminished by NSAIDs. In persons who are elderly, volume-depleted, or with compromised renal function, coadministration of ACE inhibitors and NSAIDs may result in deterioration of renal function, including possible acute renal failure; these effects are usually reversible.
Tacrolimus: (Moderate) Tacrolimus, in the absence of overt renal impairment, may adversely affect renal function. Care should be taken in using tacrolimus with other nephrotoxic drugs, including ACE inhibitors.
Telavancin: (Moderate) Concurrent or sequential use of telavancin with other potentially nephrotoxic drugs such as Angiotensin-converting enzyme inhibitors (ACE inhibitors) may lead to additive nephrotoxicity. Closely monitor renal function and adjust telavancin doses based on calculated creatinine clearance.
Telmisartan: (Major) In general, avoid combined use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) due to lack of benefit with concomitant use in most patients. Closely monitor blood pressure, renal function, and electrolytes in patients on ACE inhibitors and ARBs. Dual blockade of the renin-angiotensin system with ACE inhibitors and ARBs is associated with increased risks of hypotension, syncope, hyperkalemia, and changes in renal function, including acute renal failure, compared to monotherapy.
Telmisartan; Amlodipine: (Major) In general, avoid combined use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) due to lack of benefit with concomitant use in most patients. Closely monitor blood pressure, renal function, and electrolytes in patients on ACE inhibitors and ARBs. Dual blockade of the renin-angiotensin system with ACE inhibitors and ARBs is associated with increased risks of hypotension, syncope, hyperkalemia, and changes in renal function, including acute renal failure, compared to monotherapy.
Telmisartan; Hydrochlorothiazide, HCTZ: (Major) Discontinue the thiazide diuretic prior to starting captopril, if possible, or start captopril at the lower dose of 6.25 or 12.5 mg/day. Monitor blood pressure, particularly when doses are increased, and renal function during concomitant use. Concomitant use may increase the risk for hypotension or renal failure. (Major) In general, avoid combined use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) due to lack of benefit with concomitant use in most patients. Closely monitor blood pressure, renal function, and electrolytes in patients on ACE inhibitors and ARBs. Dual blockade of the renin-angiotensin system with ACE inhibitors and ARBs is associated with increased risks of hypotension, syncope, hyperkalemia, and changes in renal function, including acute renal failure, compared to monotherapy.
Temsirolimus: (Moderate) Monitor for signs and symptoms of angioedema if temsirolimus is administered concomitantly with captopril. Angioedema has been reported in patients taking mammalian target of rapamycin (mTOR) inhibitors in combination with another ACE inhibitor.
Tetrabenazine: (Moderate) Tetrabenazine may induce orthostatic hypotension and thus enhance the hypotensive effects of antihypertensive agents. Lower initial doses or slower dose titration of tetrabenazine may be necessary in patients receiving antihypertensive agents concomitantly.
Tetracaine: (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents. Use extreme caution with the concomitant use of tetracaine and antihypertensive agents.
Thiazide diuretics: (Major) Discontinue the thiazide diuretic prior to starting captopril, if possible, or start captopril at the lower dose of 6.25 or 12.5 mg/day. Monitor blood pressure, particularly when doses are increased, and renal function during concomitant use. Concomitant use may increase the risk for hypotension or renal failure.
Thiazolidinediones: (Moderate) Monitor blood glucose during concomitant thiazolidinedione and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Thiothixene: (Moderate) Thiothixene should be used cautiously in patients receiving antihypertensive agents. Additive hypotensive effects are possible.
Tirzepatide: (Moderate) Monitor blood glucose during concomitant incretin mimetic and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Tizanidine: (Moderate) Concurrent use of tizanidine with antihypertensive agents can result in significant hypotension. Caution is advised when tizanidine is to be used in patients receiving concurrent antihypertensive therapy.
Tolmetin: (Moderate) Monitor blood pressure and renal function periodically during concomitant angiotensin-converting enzyme (ACE) inhibitor and nonsteroidal anti-inflammatory drug (NSAID) use. The antihypertensive effect of ACE inhibitors may be diminished by NSAIDs. In persons who are elderly, volume-depleted, or with compromised renal function, coadministration of ACE inhibitors and NSAIDs may result in deterioration of renal function, including possible acute renal failure; these effects are usually reversible.
Tolvaptan: (Moderate) Monitor serum potassium concentrations closely if tolvaptan and angiotensin-converting enzyme inhibitors (ACE inhibitors) are used together. In clinical studies, hyperkalemia was reported at a rate 1% to 2% higher when tolvaptan was administered with ACE inhibitors compared to administration of these medications with placebo.
Torsemide: (Major) Discontinue the loop diuretic prior to starting captopril, if possible, or start captopril at the lower dose of 6.25 or 12.5 mg/day. Monitor blood pressure and renal function during concomitant use, particularly when doses are increased. Concomitant use may increase the risk for hypotension or renal failure.
Tranylcypromine: (Contraindicated) The use of hypotensive agents and tranylcypromine is contraindicated by the manufacturer of tranylcypromine because the effects of hypotensive agents may be markedly potentiated.
Trazodone: (Minor) Due to additive hypotensive effects, patients receiving antihypertensive agents concurrently with trazodone may have excessive hypotension. Decreased dosage of the antihypertensive agent may be required when given with trazodone.
Triamterene: (Moderate) Monitor serum potassium concentrations closely if ACE inhibitors and triamterene are used together. Concomitant use may increase the risk of hyperkalemia, especially in elderly patients or patients with impaired renal function.
Triamterene; Hydrochlorothiazide, HCTZ: (Major) Discontinue the thiazide diuretic prior to starting captopril, if possible, or start captopril at the lower dose of 6.25 or 12.5 mg/day. Monitor blood pressure, particularly when doses are increased, and renal function during concomitant use. Concomitant use may increase the risk for hypotension or renal failure. (Moderate) Monitor serum potassium concentrations closely if ACE inhibitors and triamterene are used together. Concomitant use may increase the risk of hyperkalemia, especially in elderly patients or patients with impaired renal function.
Trimethoprim: (Moderate) Monitor for hyperkalemia if concomitant use of an angiotensin-converting enzyme (ACE) inhibitor and trimethoprim is necessary. Avoid concomitant use and consider alternative antibiotic therapy in patients with additional risk factors for hyperkalemia, including patients older than 65 years, those with underlying disorders of potassium metabolism, renal insufficiency, or those requiring high doses of trimethoprim. Amongst patients older than 65 years, concomitant use has been associated with a 2- to 7-fold increased risk of significant hyperkalemia compared to other antibiotics. Trimethoprim has a potassium-sparing effect on the distal nephron and may induce hyperkalemia, especially in those with pre-existing risk factors.
Valsartan: (Major) In general, avoid combined use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) due to lack of benefit with concomitant use in most patients. Closely monitor blood pressure, renal function, and electrolytes in patients on ACE inhibitors and ARBs. Dual blockade of the renin-angiotensin system with ACE inhibitors and ARBs is associated with increased risks of hypotension, syncope, hyperkalemia, and changes in renal function, including acute renal failure, compared to monotherapy.
Valsartan; Hydrochlorothiazide, HCTZ: (Major) Discontinue the thiazide diuretic prior to starting captopril, if possible, or start captopril at the lower dose of 6.25 or 12.5 mg/day. Monitor blood pressure, particularly when doses are increased, and renal function during concomitant use. Concomitant use may increase the risk for hypotension or renal failure. (Major) In general, avoid combined use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) due to lack of benefit with concomitant use in most patients. Closely monitor blood pressure, renal function, and electrolytes in patients on ACE inhibitors and ARBs. Dual blockade of the renin-angiotensin system with ACE inhibitors and ARBs is associated with increased risks of hypotension, syncope, hyperkalemia, and changes in renal function, including acute renal failure, compared to monotherapy.
Vitamin B Complex Supplements: (Moderate) Cutaneous vasodilation induced by niacin may become problematic if high-dose niacin is used concomitantly with other antihypertensive agents. This effect is of particular concern in the setting of acute myocardial infarction, unstable angina, or other acute hemodynamic compromise.
Ziprasidone: (Minor) Ziprasidone is a moderate antagonist of alpha-1 receptors and may cause orthostatic hypotension with or without tachycardia, dizziness, or syncope. Additive hypotensive effects are possible if ziprasidone is used concurrently with antihypertensive agents.
Captopril has a high affinity for ACE and competes with angiotensin I, the natural substrate, to block its conversion to angiotensin II. Angiotensin II is a potent vasoconstrictor and a negative feedback mediator for renin activity. Thus, as a result of lower angiotensin II plasma levels, blood pressure decreases and plasma renin activity increases. In addition, baroreceptor reflex mechanisms are stimulated by the drop in blood pressure. Kininase II, identical to ACE, is an enzyme that degrades bradykinin, a potent vasodilator, to inactive peptides. Whether increased bradykinin levels play a part in the therapeutic effects of ACE inhibitors is presently unclear. Bradykinin-induced vasodilation is thought to be of secondary importance in the blood-pressure lowering effect of ACE inhibitors. A bradykinin mechanism may, however, contribute to ACE-inhibitor-induced angioneurotic edema and cough.
The "local" activity of ACE inhibitors may be more responsible for their clinical effects than systemic activity. ACE-inhibiting drugs may act locally (i.e., within a specific tissue) to reduce vascular tone by decreasing local angiotensin II-induced sympathetic activity and/or by decreasing local angiotensin II-induced vasoconstrictive activity. ACE inhibitors may inhibit presynaptic norepinephrine release and postsynaptic adrenergic receptor activity, decreasing vascular sensitivity to vasopressor activity. Decreases in plasma angiotensin II levels reduce aldosterone secretion, with a subsequent decrease in sodium and water retention.
Captopril dilates arterioles, thereby lowering total peripheral vascular resistance. In hypertensive patients, blood pressure is decreased with little or no change in heart rate, stroke volume, or cardiac output. However, captopril can increase cardiac output, cardiac index, stroke volume, and exercise tolerance in patients with congestive heart failure. The drug also decreases pulmonary wedge pressure, pulmonary vascular resistance, and mean arterial and right atrial pressures in these patients. As antihypertensives, ACE inhibitors reduce LVH, do not worsen insulin resistance or hyperlipidemia, and do not cause sexual dysfunction.
Captopril is administered orally. Captopril distributes into most body tissues, and approximately 25% is bound to proteins. The drug is metabolized (50%) in the liver to inactive metabolites, followed by excretion of the unchanged drug and its metabolites in the urine. Captopril renal elimination occurs primarily by tubular excretion. In patients with normal renal function, the half-life of captopril is less than 2 hours.
Affected cytochrome P450 isoenzymes and drug transporters: P-glycoprotein (P-gp)
Captopril is an inhibitor of P-gp and may increase the plasma concentrations of drugs that are substrates of P-gp.
-Route-Specific Pharmacokinetics
Oral Route
After oral administration, captopril is rapidly absorbed from the GI tract. If given with food, absorption decreases by 30% to 40%. Noticeable antihypertensive effects begin within 15 minutes; maximum beneficial effects require several weeks of therapy. The effects of a dose of captopril generally last about 2 to 6 hours, but the duration of action can be prolonged in patients with renal dysfunction.
-Special Populations
Renal Impairment
The pharmacokinetics of captopril may be significantly affected by renal impairment and hemodialysis. The rate of urinary captopril excretion decreases with reduced creatinine clearance (0 to 56 mL/minute); the half-life of captopril significantly increases to over 20 to 40 hours in patients with CrCl < 20 mL/minute. The half-life of captopril can be as long as 6.5 days in anuric patients. Captopril is significantly removed by dialysis. Captopril elimination is not independently affected by age or congestive heart failure; however associated renal dysfunction may reduce captopril clearance.
Pediatrics
Children and Adolescents
The half-life, clearance, and Tmax of captopril in 8 normotensive children and adolescents (5 to 18 years of age) with renal scarring after an oral dose of 0.7 mg/kg were 0.98 to 2.3 hours (mean 1.5 hours), 0.46 to 3.58 L/hour/kg (mean 1.74 L/hour/kg), and 0.5 to 2 hours, respectively.
Infants
The half-life of captopril in infants with congestive heart failure may be prolonged compared to older pediatric patients and adults. The mean half-life, clearance, and Tmax of captopril in 10 infants with congestive heart failure after an oral dose of 1 mg/kg were 1.2 to 12.4 hours (median 2 hours), 0.7 to 2.1 L/hour/kg (median 0.9 L/hour/kg), and 1 to 2 hours (median 1.5 hours), respectively.