Triamterene is a potassium-sparing, distal tubule diuretic. It is similar in action to amiloride, but triamterene increases the urinary excretion of magnesium while amiloride does not. Triamterene is a relatively weak diuretic and antihypertensive and is most often used in the management of hypokalemia, especially in patients who cannot tolerate or have been unresponsive to potassium supplements. The diuretic activity of triamterene was originally described in 1961 and it was approved by the FDA in 1964.
General Administration Information
For storage information, see the specific product information within the How Supplied section.
Route-Specific Administration
Oral Administration
-Generally, administer triamterene after meals to minimize GI adverse effects.
Triamterene-induced hyperkalemia occurs rarely. Signs and symptoms of hyperkalemia include reduced muscular strength, paresthesia, fatigue, flaccid paralysis of the extremities, sinus bradycardia, shock, and ECG changes that may lead to serious cardiac arrhythmias. Geriatric patients, severely ill patients, or patients with impaired renal function who are receiving triamterene therapy are particularly at risk for developing hyperkalemia, and periodic serum electrolyte, creatinine, and BUN determinations should be made. If hyperkalemia occurs, triamterene should be discontinued immediately, and specific measures should be taken to reduce serum potassium levels. According to the manufacturer, hypokalemia has also been reported rarely during triamterene therapy.
Electrolyte imbalance may be aggravated or caused independently by triamterene. The use of full doses of a diuretic when salt intake is restricted can result in a low-salt syndrome (hyponatremia). Triamterene therapy may cause decreased milk alkali reserve, and possibly metabolic acidosis.
Rarely, patients with alcoholic cirrhosis who received triamterene therapy have developed megaloblastic anemia. Thrombocytopenia has also occurred rarely during triamterene therapy.
Adverse GI effects reported rarely during triamterene therapy include jaundice, liver enzyme abnormalities, nausea/vomiting, and diarrhea. Nausea/vomiting can be reduced by administering the drug after meals but can also indicate electrolyte imbalance.
Adverse nervous system effects reported rarely in patients receiving triamterene therapy include headache, weakness, fatigue, dizziness, and xerostomia (dry mouth). Muscular weakness may be a sign of triamterene-induced hyperkalemia.
Adverse renal effects rarely reported with triamterene include azotemia, acute interstitial nephritis, nephrolithiasis, acute renal failure (unspecified), and elevated creatinine concentrations.
Hypersensitivity reactions including anaphylaxis (anaphylactoid reactions), photosensitivity, and rash (unspecified) have also been reported rarely during triamterene therapy. According to the manufacturer, due to the isolated reports of hypersensitivity reactions, patients should be monitored for the potential occurrence of blood dyscrasias, hepatic injury, or other idiosyncratic reactions.
Due to the diuretic action of triamterene, increased urinary frequency can be troublesome for some patients during therapy.
Elevated uric acid (hyperuricemia) has been reported during triamterene therapy, especially in patients predisposed to gouty arthritis.
Triamterene and quinidine have similar fluorescence spectra; thus, triamterene will interfere with fluorescent laboratory tests for the measurement of quinidine.
Triamterene is contraindicated in patients with hyperkalemia (potassium levels greater than 5.5 mEq/L ) or in those receiving other potassium-sparing agents. Patients receiving triamterene should not receive potassium supplementation or increase their dietary intake of potassium unless they have refractory hypokalemia; serum potassium, creatinine, and BUN levels should be monitored. Triamterene-induced hyperkalemia can cause life-threatening cardiac arrhythmias and is more likely to occur in patients with impaired renal function, diabetes mellitus, or in elderly patients; these patients should have periodic serum electrolyte, creatinine, and BUN levels monitored. Triamterene should be used with caution in these patients. The precaution for triamterene in patients with diabetes mellitus is primarily due to the risk of hyperkalemia and not the risk of inducing hyperglycemia, which may occur with thiazide or loop diuretics. Triamterene is also contraindicated in patients with anuria or any renal disease associated with severe renal impairment (i.e., CrCl less than 10 mL/min) or renal failure. Serum potassium, creatinine, and BUN levels should be monitored in patients receiving triamterene.
Triamterene should be used with caution in patients with preexisting hyponatremia. Triamterene may worsen this condition.
Patients with significant acid/base imbalance should have their condition corrected before diuretics, such as triamterene, are initiated. Close monitoring of the acid-base status is required in debilitated patients or severely ill patients in whom respiratory acidosis or metabolic acidosis may occur (e.g., cardiopulmonary disease or uncontrolled diabetes). These patients are at a higher risk for developing sudden metabolic acidosis or respiratory acidosis, with resultant rapid increases in serum potassium concentrations that could be exacerbated by potassium-sparing diuretic therapy.
Triamterene is contraindicated in patients with severe hepatic disease. Triamterene-induced fluctuations in serum electrolyte concentration (including potassium loss in patients with hepatic cirrhosis) can occur and precipitate hepatic encephalopathy in susceptible patients. In addition, triamterene is a weak folic acid antagonist and can contribute to the development of megaloblastic anemia in patients with depleted stores of folic acid such as occur in hepatic cirrhosis. In addition, the use of triamterene in patients with ascites due to cirrhotic liver disease has been occasionally associated with adverse effects such as renal insufficiency and bone marrow megaloblastosis. Dose reduction of triamterene may be warranted in patients with cirrhosis; cirrhosis is associated with a prolonged half-life of triamterene (by approximately four-fold).
Triamterene has been reported to be a constituent of renal stones in patients receiving the drug and therefore must be used with caution in patients predisposed to nephrolithiasis. Thiazide diuretics have been reported to reduce the clearance of uric acid. Caution should also be used when triamterene is administered to patients with gout or hyperuricemia.
No human studies have been conducted with triamterene. No evidence of harm was seen in fetuses of rats when exposed to doses as high as 20 times the maximum recommended human exposure; however, animal data are not always predictive of human response. Triamterene crosses the placenta and should only be used during pregnancy if clearly needed and only if the anticipated benefits outweigh the potential hazards to the fetus.
Triamterene should be avoided during breast-feeding. The molecular weight is low enough for the drug to be excreted in human milk; however, the effect of exposure to a nursing infant is unknown. If the use of triamterene is absolutely necessary, the patient should stop nursing. Alternatives, such as spironolactone or hydrochlorothiazide, may be preferred.
Geriatric patients should be observed carefully for possible serum potassium increases while receiving triamterene. Hyperkalemia is more likely to occur in the older adult patient. According to the Beers Criteria, diuretics are considered potentially inappropriate medications (PIMs) in geriatric adults; use with caution due to the potential for causing or exacerbating SIADH or hyponatremia. Sodium levels should be closely monitored when starting or changing dosages of diuretics in older adults. Avoid triamterene in those with a creatinine clearance less than 30 mL/minute due to the potential for increased potassium and decreased sodium.
For the treatment of peripheral edema states (e.g., heart failure, idiopathic edema, nephrotic syndrome, ascites due to hepatic cirrhosis, secondary hyperaldosteronism), hypertension*, or hypokalemia:
Oral dosage:
Adults: 100 mg PO twice daily. Use lower initial dose when used in combination with another diuretic or antihypertensive agent. Max: 300 mg/day PO.
Children* and Adolescents*: 1 to 4 mg/kg/day PO in 2 divided doses. Max: 300 mg/day.
For the treatment of symptoms of bloating and weight gain associated with premenstrual syndrome (PMS)*:
Oral dosage:
Adults: 50-100 mg PO, given once daily or twice daily. Diuretic use should be limited to patients who demonstrate a premenstrual weight gain of > 1.4 kg. Dosage should be titrated to achieve desired diuresis and to minimize weight gain.
Maximum Dosage Limits:
-Adults
300 mg/day PO.
-Elderly
300 mg/day PO.
-Adolescents
300 mg/day PO.
-Children
6 mg/kg/day PO or 300 mg/day PO, whichever is less.
Patients with Hepatic Impairment Dosing
Dose reduction may be warranted; cirrhosis is associated with a prolonged half-life of triamterene (by approximately four-fold).
Patients with Renal Impairment Dosing
CrCl 10 mL/minute or more: No dosage adjustment needed. Use with caution in patients with CrCl less than 30 mL/minute since hyperkalemia is more common in patients with renal impairment.
CrCl less than 10 mL/minute: Contraindicated. Avoid use of drug due to the potential for hyperkalemia.
Intermittent hemodialysis
Triamterene is contraindicated in patients with renal failure or anuria.
*non-FDA-approved indication
Acarbose: (Minor) Triamterene can interfere with the hypoglycemic effects of antidiabetic agents. This can lead to a loss of diabetic control, so diabetic patients should be monitored closely.
Acetaminophen; Aspirin, ASA; Caffeine: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant triamterene and salicylate use. Salicylate use decreases glomerular filtration rate and renal blood flow, and concomitant diuretic use may increase the risk of this reaction. Salicylates may diminish the effectiveness of diuretics due to inhibition of renal prostaglandins, leading to decreased renal blood flow and salt and fluid retention.
Acetaminophen; Aspirin: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant triamterene and salicylate use. Salicylate use decreases glomerular filtration rate and renal blood flow, and concomitant diuretic use may increase the risk of this reaction. Salicylates may diminish the effectiveness of diuretics due to inhibition of renal prostaglandins, leading to decreased renal blood flow and salt and fluid retention.
Acetaminophen; Aspirin; Diphenhydramine: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant triamterene and salicylate use. Salicylate use decreases glomerular filtration rate and renal blood flow, and concomitant diuretic use may increase the risk of this reaction. Salicylates may diminish the effectiveness of diuretics due to inhibition of renal prostaglandins, leading to decreased renal blood flow and salt and fluid retention.
Acetaminophen; Chlorpheniramine; Dextromethorphan; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
Acetaminophen; Chlorpheniramine; Dextromethorphan; Pseudoephedrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine 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; Phenylephrine : (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
Acetaminophen; Codeine: (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of triamterene and codeine; increase the dosage of triamterene as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone.
Acetaminophen; Dextromethorphan; Guaifenesin; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
Acetaminophen; Dextromethorphan; Guaifenesin; Pseudoephedrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine 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; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
Acetaminophen; Dextromethorphan; Pseudoephedrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine 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; Guaifenesin; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
Acetaminophen; Hydrocodone: (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of triamterene and hydrocodone; increase the dosage of triamterene as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone.
Acetaminophen; Ibuprofen: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant triamterene and ibuprofen use. Nonsteroidal antiinflammatory drugs (NSAIDs) may cause a dose-dependent reduction in renal blood flow, which may precipitate overt renal decompensation, and concomitant diuretic use increases the risk of this reaction. NSAIDs are associated with fluid retention which may blunt the cardiovascular effects of diuretics.
Acetaminophen; Oxycodone: (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of triamterene and oxycodone; increase the dosage of triamterene as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone.
Acetaminophen; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
Acetaminophen; Pseudoephedrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine 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.
Acetazolamide: (Moderate) Carbonic anhydrase inhibitors promote electrolyte excretion including hydrogen ions, sodium, and potassium. They can enhance the sodium depleting effects of other diuretics when used concurrently. Pre-existing hypokalemia and hyperuricemia can also be potentiated by carbonic anhydrase inhibitors. Monitor serum potassium to determine the need for potassium supplementation and alteration in drug therapy.
Acrivastine; Pseudoephedrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine 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.
Adefovir: (Moderate) Adefovir is eliminated renally by a combination of glomerular filtration and active tubular secretion; coadministration of adefovir dipivoxil with drugs that reduce renal function or compete for active tubular secretion, such as triamterene, may decrease adefovir elimination by competing for common renal tubular transport systems, thereby increasing serum concentrations of adefovir and/or triamterene.
Albuterol; Budesonide: (Minor) The manufacturer of spironolactone lists corticosteroids as a potential drug that interacts with spironolactone. Intensified electrolyte depletion, particularly hypokalemia, may occur. However, potassium-sparing diuretics such as spironolactone do not induce hypokalemia. In fact, hypokalemia is one of the indications for potassium-sparing diuretic therapy. Therefore, drugs that induce potassium loss, such as corticosteroids, could counter the hyperkalemic effects of potassium-sparing diuretics.
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.
Alfentanil: (Moderate) Monitor for decreased diuretic efficacy and additive orthostatic hypotension when triamterene is administered with alfentanil. Adjustments to diuretic therapy may be needed in some patients. The efficacy of diuretics may be reduced due to opioid-induced release of antidiuretic hormone.
Aliskiren: (Moderate) Due to the risk of hyperkalemia, drugs that increase serum potassium concentration, such as potassium-sparing diuretics, should be used cautiously in patients taking aliskiren. Electrolytes should be routinely monitored in patients receiving aliskiren. Aliskiren can enhance the effects of diuretics on blood pressure if given concomitantly. This additive effect may be desirable, but dosages must be adjusted accordingly. Also, patients with hyponatremia or hypovolemia may become hypotensive and/or develop reversible renal insufficiency when given aliskiren and diuretics.
Aliskiren; Hydrochlorothiazide, HCTZ: (Moderate) Due to the risk of hyperkalemia, drugs that increase serum potassium concentration, such as potassium-sparing diuretics, should be used cautiously in patients taking aliskiren. Electrolytes should be routinely monitored in patients receiving aliskiren. Aliskiren can enhance the effects of diuretics on blood pressure if given concomitantly. This additive effect may be desirable, but dosages must be adjusted accordingly. Also, patients with hyponatremia or hypovolemia may become hypotensive and/or develop reversible renal insufficiency when given aliskiren and diuretics.
Alogliptin: (Minor) Triamterene can interfere with the hypoglycemic effects of antidiabetic agents, such as alogliptin, by producing an increase in blood glucose concentrations. It appears that the effects of triamterene on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, thiazide diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients receiving alogliptin should be monitored for changes in blood glucose control if triamterene is added or deleted. Dosage adjustments may be necessary.
Alogliptin; Metformin: (Minor) Triamterene can interfere with the hypoglycemic effects of antidiabetic agents, such as alogliptin, by producing an increase in blood glucose concentrations. It appears that the effects of triamterene on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, thiazide diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients receiving alogliptin should be monitored for changes in blood glucose control if triamterene is added or deleted. Dosage adjustments may be necessary.
Alogliptin; Pioglitazone: (Minor) Triamterene can interfere with the hypoglycemic effects of antidiabetic agents, such as alogliptin, by producing an increase in blood glucose concentrations. It appears that the effects of triamterene on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, thiazide diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients receiving alogliptin should be monitored for changes in blood glucose control if triamterene is added or deleted. Dosage adjustments may be necessary. (Minor) Triamterene can interfere with the hypoglycemic effects of antidiabetic agents. This can lead to a loss of diabetic control, so diabetic patients should be monitored closely.
Alpha-glucosidase Inhibitors: (Minor) Triamterene can interfere with the hypoglycemic effects of antidiabetic agents. This can lead to a loss of diabetic control, so diabetic patients should be monitored closely.
Alprostadil: (Minor) The concomitant use of systemic alprostadil injection and antihypertensive agents, such as spironolactone or other potassium-sparing diuretics, 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. In addition, the presence of medications in the circulation that attenuate erectile function may influence the response to alprostadil. However, in clinical trials with alprostadil intracavernous injection, anti-hypertensive agents had no apparent effect on the safety and efficacy of alprostadil.
Amantadine: (Minor) Use caution. Triamterene can reduce the renal clearance of amantadine, with subsequent increased amantadine serum concentrations. The clinical significance is not known. Monitor for possible side effects of amantadine, including dizziness, confusion, nausea/vomiting, xerostomia, and anticholinergic effects.
Ambrisentan: (Moderate) Although no specific interactions have been documented, ambrisentan has vasodilatory effects and may contribute additive hypotensive effects when given with other antihypertensive agents. Patients receiving ambrisentan in combination with other antihypertensive agents should be monitored for decreases in blood pressure.
Amifostine: (Major) Patients receiving antihypertensive agents should be closely monitored during amifostine infusions due to additive effects. If possible, patients should not take their antihypertensive medication 24 hours before receiving amifostine. Patients who can not stop their antihypertensive agents should not receive amifostine or be closely monitored during the infusion and, possibly, given lower doses.
Aminosalicylate sodium, Aminosalicylic acid: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant triamterene and salicylate use. Salicylate use decreases glomerular filtration rate and renal blood flow, and concomitant diuretic use may increase the risk of this reaction. Salicylates may diminish the effectiveness of diuretics due to inhibition of renal prostaglandins, leading to decreased renal blood flow and salt and fluid retention.
Amlodipine; Benazepril: (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.
Amlodipine; Celecoxib: (Moderate) Nonsteroidal anti-inflammatory drugs (NSAIDs), including COX-2 inhibitors, may reduce the natriuretic effect of diuretics in some patients. NSAIDS have been associated with an inhibition of prostaglandin synthesis, which may result in reduced renal blood flow leading to renal insufficiency and increases in blood pressure that are often accompanied by peripheral edema and weight gain. Patients taking diuretics and NSAIDS concurrently are at higher risk of developing renal insufficiency. If celecoxib and a diuretic are used concurrently, carefully monitor the patient for signs and symptoms of decreased renal function and diuretic efficacy.
Amlodipine; Olmesartan: (Moderate) Monitor serum potassium concentrations in patients receiving angiotensin II receptor antagonists concomitantly with triamterene. Concomitant use may result in hyperkalemia.
Amlodipine; Valsartan: (Moderate) Monitor serum potassium concentrations in patients receiving angiotensin II receptor antagonists concomitantly with triamterene. Concomitant use may result in hyperkalemia.
Amlodipine; Valsartan; Hydrochlorothiazide, HCTZ: (Moderate) Monitor serum potassium concentrations in patients receiving angiotensin II receptor antagonists concomitantly with triamterene. Concomitant use may result in hyperkalemia.
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 potassium-sparing diuretics. 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 potassium-sparing diuretics. 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 potassium-sparing diuretics. Close monitoring of blood pressure is advised.
Angiotensin II receptor antagonists: (Moderate) Monitor serum potassium concentrations in patients receiving angiotensin II receptor antagonists concomitantly with triamterene. Concomitant use may result in hyperkalemia.
Angiotensin-converting enzyme inhibitors: (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.
Apomorphine: (Moderate) Use of potassium-sparing diuretics 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.
Aripiprazole: (Moderate) Monitor blood pressure during concurrent use of triamterene; a triamterene dose adjustment may be needed. Due to its alpha-adrenergic antagonism, aripiprazole has the potential to enhance the effect of certain antihypertensive agents.
Arsenic Trioxide: (Moderate) Use caution when using arsenic trioxide with potassium-sparing diuretics. Electrolyte abnormalities, such as increased potassium, may increase the risk for QT prolongation and torsade de pointes.
Articaine; Epinephrine: (Moderate) Monitor blood pressure and heart rate during concomitant epinephrine and potassium-sparing diuretic use. Potassium-sparing diuretics may antagonize the pressor effects and potentiate the arrhythmogenic effects of 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) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant triamterene and salicylate use. Salicylate use decreases glomerular filtration rate and renal blood flow, and concomitant diuretic use may increase the risk of this reaction. Salicylates may diminish the effectiveness of diuretics due to inhibition of renal prostaglandins, leading to decreased renal blood flow and salt and fluid retention.
Aspirin, ASA; Butalbital; Caffeine: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant triamterene and salicylate use. Salicylate use decreases glomerular filtration rate and renal blood flow, and concomitant diuretic use may increase the risk of this reaction. Salicylates may diminish the effectiveness of diuretics due to inhibition of renal prostaglandins, leading to decreased renal blood flow and salt and fluid retention.
Aspirin, ASA; Caffeine: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant triamterene and salicylate use. Salicylate use decreases glomerular filtration rate and renal blood flow, and concomitant diuretic use may increase the risk of this reaction. Salicylates may diminish the effectiveness of diuretics due to inhibition of renal prostaglandins, leading to decreased renal blood flow and salt and fluid retention.
Aspirin, ASA; Caffeine; Orphenadrine: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant triamterene and salicylate use. Salicylate use decreases glomerular filtration rate and renal blood flow, and concomitant diuretic use may increase the risk of this reaction. Salicylates may diminish the effectiveness of diuretics due to inhibition of renal prostaglandins, leading to decreased renal blood flow and salt and fluid retention.
Aspirin, ASA; Carisoprodol; Codeine: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant triamterene and salicylate use. Salicylate use decreases glomerular filtration rate and renal blood flow, and concomitant diuretic use may increase the risk of this reaction. Salicylates may diminish the effectiveness of diuretics due to inhibition of renal prostaglandins, leading to decreased renal blood flow and salt and fluid retention. (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of triamterene and codeine; increase the dosage of triamterene as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone.
Aspirin, ASA; Citric Acid; Sodium Bicarbonate: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant triamterene and salicylate use. Salicylate use decreases glomerular filtration rate and renal blood flow, and concomitant diuretic use may increase the risk of this reaction. Salicylates may diminish the effectiveness of diuretics due to inhibition of renal prostaglandins, leading to decreased renal blood flow and salt and fluid retention.
Aspirin, ASA; Dipyridamole: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant triamterene and salicylate use. Salicylate use decreases glomerular filtration rate and renal blood flow, and concomitant diuretic use may increase the risk of this reaction. Salicylates may diminish the effectiveness of diuretics due to inhibition of renal prostaglandins, leading to decreased renal blood flow and salt and fluid retention.
Aspirin, ASA; Omeprazole: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant triamterene and salicylate use. Salicylate use decreases glomerular filtration rate and renal blood flow, and concomitant diuretic use may increase the risk of this reaction. Salicylates may diminish the effectiveness of diuretics due to inhibition of renal prostaglandins, leading to decreased renal blood flow and salt and fluid retention.
Aspirin, ASA; Oxycodone: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant triamterene and salicylate use. Salicylate use decreases glomerular filtration rate and renal blood flow, and concomitant diuretic use may increase the risk of this reaction. Salicylates may diminish the effectiveness of diuretics due to inhibition of renal prostaglandins, leading to decreased renal blood flow and salt and fluid retention. (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of triamterene and oxycodone; increase the dosage of triamterene as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone.
Azelastine; Fluticasone: (Minor) The manufacturer of spironolactone lists corticosteroids as a potential drug that interacts with spironolactone. Intensified electrolyte depletion, particularly hypokalemia, may occur. However, potassium-sparing diuretics such as spironolactone do not induce hypokalemia. In fact, hypokalemia is one of the indications for potassium-sparing diuretic therapy. Therefore, drugs that induce potassium loss, such as corticosteroids, could counter the hyperkalemic effects of potassium-sparing diuretics.
Azilsartan: (Moderate) Monitor serum potassium concentrations in patients receiving angiotensin II receptor antagonists concomitantly with triamterene. Concomitant use may result in hyperkalemia.
Azilsartan; Chlorthalidone: (Moderate) Monitor serum potassium concentrations in patients receiving angiotensin II receptor antagonists concomitantly with triamterene. Concomitant use may result in hyperkalemia.
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.
Beclomethasone: (Minor) The manufacturer of spironolactone lists corticosteroids as a potential drug that interacts with spironolactone. Intensified electrolyte depletion, particularly hypokalemia, may occur. However, potassium-sparing diuretics such as spironolactone do not induce hypokalemia. In fact, hypokalemia is one of the indications for potassium-sparing diuretic therapy. Therefore, drugs that induce potassium loss, such as corticosteroids, could counter the hyperkalemic effects of potassium-sparing diuretics.
Belladonna; Opium: (Moderate) Monitor for decreased diuretic efficacy and additive orthostatic hypotension when triamterene is administered with opium. Adjustments to diuretic therapy may be needed in some patients. The efficacy of diuretics may be reduced due to opioid-induced release of antidiuretic hormone.
Benazepril: (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.
Benazepril; Hydrochlorothiazide, HCTZ: (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.
Benzhydrocodone; Acetaminophen: (Moderate) Monitor for decreased diuretic efficacy and additive orthostatic hypotension when triamterene is administered with benzhydrocodone. Adjustments to diuretic therapy may be needed in some patients. The efficacy of diuretics may be reduced due to opioid-induced release of antidiuretic hormone.
Benzoic Acid; Hyoscyamine; Methenamine; Methylene Blue; Phenyl Salicylate: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant triamterene and salicylate use. Salicylate use decreases glomerular filtration rate and renal blood flow, and concomitant diuretic use may increase the risk of this reaction. Salicylates may diminish the effectiveness of diuretics due to inhibition of renal prostaglandins, leading to decreased renal blood flow and salt and fluid retention.
Benzphetamine: (Minor) Benzphetamine may increase both systolic and diastolic blood pressure and may counteract the activity of some antihypertensive agents, like potassium-sparing diuretics. Close monitoring of blood pressure is advised.
Betamethasone: (Minor) The manufacturer of spironolactone lists corticosteroids as a potential drug that interacts with spironolactone. Intensified electrolyte depletion, particularly hypokalemia, may occur. However, potassium-sparing diuretics such as spironolactone do not induce hypokalemia. In fact, hypokalemia is one of the indications for potassium-sparing diuretic therapy. Therefore, drugs that induce potassium loss, such as corticosteroids, could counter the hyperkalemic effects of potassium-sparing diuretics.
Bismuth Subsalicylate: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant triamterene and salicylate use. Salicylate use decreases glomerular filtration rate and renal blood flow, and concomitant diuretic use may increase the risk of this reaction. Salicylates may diminish the effectiveness of diuretics due to inhibition of renal prostaglandins, leading to decreased renal blood flow and salt and fluid retention.
Bismuth Subsalicylate; Metronidazole; Tetracycline: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant triamterene and salicylate use. Salicylate use decreases glomerular filtration rate and renal blood flow, and concomitant diuretic use may increase the risk of this reaction. Salicylates may diminish the effectiveness of diuretics due to inhibition of renal prostaglandins, leading to decreased renal blood flow and salt and fluid retention.
Bortezomib: (Moderate) Patients on antihypertensive agents receiving bortezomib treatment may require close monitoring of their blood pressure and dosage adjustment of their medication. During clinical trials of bortezomib, hypotension was reported in roughly 12 percent of patients.
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 diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
Brompheniramine; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
Brompheniramine; Pseudoephedrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine 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; Dextromethorphan: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine 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.
Budesonide: (Minor) The manufacturer of spironolactone lists corticosteroids as a potential drug that interacts with spironolactone. Intensified electrolyte depletion, particularly hypokalemia, may occur. However, potassium-sparing diuretics such as spironolactone do not induce hypokalemia. In fact, hypokalemia is one of the indications for potassium-sparing diuretic therapy. Therefore, drugs that induce potassium loss, such as corticosteroids, could counter the hyperkalemic effects of potassium-sparing diuretics.
Budesonide; Formoterol: (Minor) The manufacturer of spironolactone lists corticosteroids as a potential drug that interacts with spironolactone. Intensified electrolyte depletion, particularly hypokalemia, may occur. However, potassium-sparing diuretics such as spironolactone do not induce hypokalemia. In fact, hypokalemia is one of the indications for potassium-sparing diuretic therapy. Therefore, drugs that induce potassium loss, such as corticosteroids, could counter the hyperkalemic effects of potassium-sparing diuretics.
Budesonide; Glycopyrrolate; Formoterol: (Minor) The manufacturer of spironolactone lists corticosteroids as a potential drug that interacts with spironolactone. Intensified electrolyte depletion, particularly hypokalemia, may occur. However, potassium-sparing diuretics such as spironolactone do not induce hypokalemia. In fact, hypokalemia is one of the indications for potassium-sparing diuretic therapy. Therefore, drugs that induce potassium loss, such as corticosteroids, could counter the hyperkalemic effects of potassium-sparing diuretics.
Bupivacaine; Epinephrine: (Moderate) Monitor blood pressure and heart rate during concomitant epinephrine and potassium-sparing diuretic use. Potassium-sparing diuretics may antagonize the pressor effects and potentiate the arrhythmogenic effects of epinephrine.
Bupivacaine; Meloxicam: (Moderate) Nonsteroidal anti-inflammatory drugs (NSAIDs) may reduce the natriuretic effect of diuretics in some patients. NSAIDS have been associated with an inhibition of prostaglandin synthesis, which may result in reduced renal blood flow leading to renal insufficiency and increases in blood pressure that are often accompanied by peripheral edema and weight gain. Patients taking diuretics and NSAIDS concurrently are at higher risk of developing renal insufficiency. If an NSAID and a diuretic are used concurrently, carefully monitor the patient for signs and symptoms of decreased renal function and diuretic efficacy.
Buprenorphine: (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of a triamterene and buprenorphine; increase the dosage of the thiazide diuretic as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone.
Buprenorphine; Naloxone: (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of a triamterene and buprenorphine; increase the dosage of the thiazide diuretic as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone.
Butalbital; Acetaminophen; Caffeine; Codeine: (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of triamterene and codeine; increase the dosage of triamterene as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone.
Butalbital; Aspirin; Caffeine; Codeine: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant triamterene and salicylate use. Salicylate use decreases glomerular filtration rate and renal blood flow, and concomitant diuretic use may increase the risk of this reaction. Salicylates may diminish the effectiveness of diuretics due to inhibition of renal prostaglandins, leading to decreased renal blood flow and salt and fluid retention. (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of triamterene and codeine; increase the dosage of triamterene as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone.
Cabergoline: (Moderate) Cabergoline should be used cautiously with antihypertensive agents, including potassium-sparing diuretics. 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 Phosphate, Supersaturated: (Moderate) Concomitant use of medicines with potential to alter renal perfusion or function such as diuretics may increase the risk of acute phosphate nephropathy in patients receiving sodium phosphate monobasic monohydrate; sodium phosphate dibasic anhydrous.
Candesartan: (Moderate) Monitor serum potassium concentrations in patients receiving angiotensin II receptor antagonists concomitantly with triamterene. Concomitant use may result in hyperkalemia.
Candesartan; Hydrochlorothiazide, HCTZ: (Moderate) Monitor serum potassium concentrations in patients receiving angiotensin II receptor antagonists concomitantly with triamterene. Concomitant use may result in hyperkalemia.
Captopril: (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.
Captopril; Hydrochlorothiazide, HCTZ: (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.
Carbidopa; Levodopa: (Moderate) Monitor blood pressure during concomitant levodopa and potassium-sparing diuretic use due to risk for additive hypotension; a potassium-sparing diuretic dosage adjustment may be necessary. Symptomatic postural hypotension has occurred when carbidopa; levodopa was added in a person receiving antihypertensive drugs.
Carbidopa; Levodopa; Entacapone: (Moderate) Monitor blood pressure during concomitant levodopa and potassium-sparing diuretic use due to risk for additive hypotension; a potassium-sparing diuretic dosage adjustment may be necessary. Symptomatic postural hypotension has occurred when carbidopa; levodopa was added in a person receiving antihypertensive drugs.
Carbonic anhydrase inhibitors: (Moderate) Carbonic anhydrase inhibitors promote electrolyte excretion including hydrogen ions, sodium, and potassium. They can enhance the sodium depleting effects of other diuretics when used concurrently. Pre-existing hypokalemia and hyperuricemia can also be potentiated by carbonic anhydrase inhibitors. Monitor serum potassium to determine the need for potassium supplementation and alteration in drug therapy.
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) Nonsteroidal anti-inflammatory drugs (NSAIDs), including COX-2 inhibitors, may reduce the natriuretic effect of diuretics in some patients. NSAIDS have been associated with an inhibition of prostaglandin synthesis, which may result in reduced renal blood flow leading to renal insufficiency and increases in blood pressure that are often accompanied by peripheral edema and weight gain. Patients taking diuretics and NSAIDS concurrently are at higher risk of developing renal insufficiency. If celecoxib and a diuretic are used concurrently, carefully monitor the patient for signs and symptoms of decreased renal function and diuretic efficacy.
Celecoxib; Tramadol: (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of triamterene and tramadol; increase the dosage of triamterene as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone. (Moderate) Nonsteroidal anti-inflammatory drugs (NSAIDs), including COX-2 inhibitors, may reduce the natriuretic effect of diuretics in some patients. NSAIDS have been associated with an inhibition of prostaglandin synthesis, which may result in reduced renal blood flow leading to renal insufficiency and increases in blood pressure that are often accompanied by peripheral edema and weight gain. Patients taking diuretics and NSAIDS concurrently are at higher risk of developing renal insufficiency. If celecoxib and a diuretic are used concurrently, carefully monitor the patient for signs and symptoms of decreased renal function and diuretic efficacy.
Cetirizine; Pseudoephedrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine 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.
Chlophedianol; Dexchlorpheniramine; Pseudoephedrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine 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.
Chloroprocaine: (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents.
Chlorpheniramine; Codeine: (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of triamterene and codeine; increase the dosage of triamterene as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone.
Chlorpheniramine; Dextromethorphan; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
Chlorpheniramine; Dextromethorphan; Pseudoephedrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine 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; Hydrocodone: (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of triamterene and hydrocodone; increase the dosage of triamterene as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone.
Chlorpheniramine; Ibuprofen; Pseudoephedrine: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant triamterene and ibuprofen use. Nonsteroidal antiinflammatory drugs (NSAIDs) may cause a dose-dependent reduction in renal blood flow, which may precipitate overt renal decompensation, and concomitant diuretic use increases the risk of this reaction. NSAIDs are associated with fluid retention which may blunt the cardiovascular effects of diuretics. (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine 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; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
Chlorpheniramine; Pseudoephedrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine 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.
Choline Salicylate; Magnesium Salicylate: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant triamterene and salicylate use. Salicylate use decreases glomerular filtration rate and renal blood flow, and concomitant diuretic use may increase the risk of this reaction. Salicylates may diminish the effectiveness of diuretics due to inhibition of renal prostaglandins, leading to decreased renal blood flow and salt and fluid retention.
Ciclesonide: (Minor) The manufacturer of spironolactone lists corticosteroids as a potential drug that interacts with spironolactone. Intensified electrolyte depletion, particularly hypokalemia, may occur. However, potassium-sparing diuretics such as spironolactone do not induce hypokalemia. In fact, hypokalemia is one of the indications for potassium-sparing diuretic therapy. Therefore, drugs that induce potassium loss, such as corticosteroids, could counter the hyperkalemic effects of potassium-sparing diuretics.
Cidofovir: (Contraindicated) The administration of cidofovir with another potentially nephrotoxic agent, such as diuretics, is contraindicated. Diuretics should be discontinued at least 7 days prior to beginning cidofovir.
Ciprofloxacin: (Minor) Triamterene is a substrate for CYP1A2. Theoretically, the metabolism of triamterene may be affected by drugs that are inhibitors CYP1A2, such as ciprofloxacin.
Citalopram: (Moderate) Monitor for signs and symptoms of hyponatremia during concomitant diuretic and citalopram use; consider discontinuing citalopram if symptomatic hyponatremia occurs and institute appropriate medical intervention. Concomitant use increases the risk for developing hyponatremia.
Citric Acid; Potassium Citrate; Sodium Citrate: (Major) The use of potassium supplements in patients treated with triamterene is generally contraindicated. Concomitant use may increase the risk of hyperkalemia. If potassium supplementation is used, monitor serum potassium concentrations closely.
Clozapine: (Moderate) Monitor blood pressure and adjust triamterene dose accordingly as clozapine may enhance the hypotensive effects of antihypertensive agents.
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: (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of triamterene and codeine; increase the dosage of triamterene as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone.
Codeine; Guaifenesin: (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of triamterene and codeine; increase the dosage of triamterene as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone.
Codeine; Guaifenesin; Pseudoephedrine: (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of triamterene and codeine; increase the dosage of triamterene as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone. (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine 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.
Codeine; Phenylephrine; Promethazine: (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of triamterene and codeine; increase the dosage of triamterene as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone. (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
Codeine; Promethazine: (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of triamterene and codeine; increase the dosage of triamterene as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone.
Co-Enzyme Q10, Ubiquinone: (Moderate) Monitor blood pressure during concomitant co-enzyme Q10 (ubiquinone) and potassium-sparing diuretic use. Concomitant use may result in additive hypotension.
Corticosteroids: (Minor) The manufacturer of spironolactone lists corticosteroids as a potential drug that interacts with spironolactone. Intensified electrolyte depletion, particularly hypokalemia, may occur. However, potassium-sparing diuretics such as spironolactone do not induce hypokalemia. In fact, hypokalemia is one of the indications for potassium-sparing diuretic therapy. Therefore, drugs that induce potassium loss, such as corticosteroids, could counter the hyperkalemic effects of potassium-sparing diuretics.
Corticotropin, ACTH: (Minor) Monitor serum electrolytes, particularly serum calcium concentrations, during concomitant corticotropin and potassium-sparing diuretic use. Corticotropin may accentuate the electrolyte loss associated with diuretic therapy.
Cortisone: (Minor) The manufacturer of spironolactone lists corticosteroids as a potential drug that interacts with spironolactone. Intensified electrolyte depletion, particularly hypokalemia, may occur. However, potassium-sparing diuretics such as spironolactone do not induce hypokalemia. In fact, hypokalemia is one of the indications for potassium-sparing diuretic therapy. Therefore, drugs that induce potassium loss, such as corticosteroids, could counter the hyperkalemic effects of potassium-sparing diuretics.
Cosyntropin: (Moderate) Use cosyntropin cautiously in patients receiving diuretics. Cosyntropin may accentuate the electrolyte loss associated with diuretic therapy.
Cyclosporine: (Major) Avoid concomitant use of cyclosporine and potassium-sparing diuretics, such as triamterene, due to the risk of hyperkalemia. If concomitant use is necessary, closely monitor serum potassium concentrations.
Dapagliflozin; Saxagliptin: (Minor) Triamterene can interfere with the hypoglycemic effects of antidiabetic agents. This can lead to a loss of diabetic control, so diabetic patients should be monitored closely.
Darifenacin: (Minor) Diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Deflazacort: (Minor) The manufacturer of spironolactone lists corticosteroids as a potential drug that interacts with spironolactone. Intensified electrolyte depletion, particularly hypokalemia, may occur. However, potassium-sparing diuretics such as spironolactone do not induce hypokalemia. In fact, hypokalemia is one of the indications for potassium-sparing diuretic therapy. Therefore, drugs that induce potassium loss, such as corticosteroids, could counter the hyperkalemic effects of potassium-sparing diuretics.
Desloratadine; Pseudoephedrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine 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.
Desvenlafaxine: (Moderate) Monitor for signs and symptoms of hyponatremia during concomitant diuretic and serotonin norepinephrine reuptake inhibitor (SNRI) use; consider discontinuing the SNRI if symptomatic hyponatremia occurs and institute appropriate medical intervention. Concomitant use increases the risk for developing hyponatremia.
Dexamethasone: (Minor) The manufacturer of spironolactone lists corticosteroids as a potential drug that interacts with spironolactone. Intensified electrolyte depletion, particularly hypokalemia, may occur. However, potassium-sparing diuretics such as spironolactone do not induce hypokalemia. In fact, hypokalemia is one of the indications for potassium-sparing diuretic therapy. Therefore, drugs that induce potassium loss, such as corticosteroids, could counter the hyperkalemic effects of potassium-sparing diuretics.
Dexbrompheniramine; Pseudoephedrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine 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.
Dexchlorpheniramine; Dextromethorphan; Pseudoephedrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine 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.
Dexmethylphenidate: (Moderate) Monitor blood pressure during concomitant potassium-sparing diuretic and methylphenidate use; a potassium-sparing diuretic dose adjustment may be necessary. Methylphenidate may decrease the effectiveness of medications used to treat hypertension.
Dextroamphetamine: (Minor) Amphetamines increase both systolic and diastolic blood pressure and may counteract the activity of some antihypertensive agents, like potassium-sparing diuretics. Close monitoring of blood pressure is advised.
Dextromethorphan; Diphenhydramine; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
Dextromethorphan; Guaifenesin; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
Dextromethorphan; Guaifenesin; Pseudoephedrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine 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; 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.
Dichlorphenamide: (Moderate) Use dichlorphenamide and triamterene together with caution as both drugs can cause metabolic acidosis. Concurrent use may increase the severity of metabolic acidosis. Measure sodium bicarbonate concentrations at baseline and periodically during dichlorphenamide treatment. If metabolic acidosis occurs or persists, consider reducing the dose or discontinuing dichlorphenamide therapy.
Diclofenac: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant triamterene and diclofenac use. Nonsteroidal antiinflammatory drugs (NSAIDs) may cause a dose-dependent reduction in renal blood flow, which may precipitate overt renal decompensation, and concomitant diuretic use increases the risk of this reaction. NSAIDs are associated with fluid retention which may blunt the cardiovascular effects of diuretics.
Diclofenac; Misoprostol: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant triamterene and diclofenac use. Nonsteroidal antiinflammatory drugs (NSAIDs) may cause a dose-dependent reduction in renal blood flow, which may precipitate overt renal decompensation, and concomitant diuretic use increases the risk of this reaction. NSAIDs are associated with fluid retention which may blunt the cardiovascular effects of diuretics.
Diphenhydramine; Ibuprofen: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant triamterene and ibuprofen use. Nonsteroidal antiinflammatory drugs (NSAIDs) may cause a dose-dependent reduction in renal blood flow, which may precipitate overt renal decompensation, and concomitant diuretic use increases the risk of this reaction. NSAIDs are associated with fluid retention which may blunt the cardiovascular effects of diuretics.
Diphenhydramine; Naproxen: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant triamterene and naproxen use. Nonsteroidal antiinflammatory drugs (NSAIDs) may cause a dose-dependent reduction in renal blood flow, which may precipitate overt renal decompensation, and concomitant diuretic use increases the risk of this reaction. NSAIDs are associated with fluid retention which may blunt the cardiovascular effects of diuretics.
Diphenhydramine; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
Dofetilide: (Major) Drugs that are actively secreted via cationic tubular secretion, such as triamterene, should be co-administered with caution with dofetilide since they could increase dofetilide plasma concentrations via potential competition for renal cationic secretion. Increased dofetilide plasma concentrations may be associated with proarrhythmias.
Donepezil; Memantine: (Minor) Memantine is excreted in part by renal tubular secretion. Competition of memantine for excretion with other drugs that are also eliminated by tubular secretion, such as triamterene, could result in elevated serum concentrations of one or both drugs.
Drospirenone: (Moderate) Monitor serum potassium concentration during concomitant drospirenone and potassium-sparing diuretic use due to increased risk for hyperkalemia. Drospirenone has anti-mineralocorticoid activity, including the potential for hyperkalemia.
Drospirenone; Estetrol: (Moderate) Monitor serum potassium concentration during concomitant drospirenone and potassium-sparing diuretic use due to increased risk for hyperkalemia. Drospirenone has anti-mineralocorticoid activity, including the potential for hyperkalemia.
Drospirenone; Estradiol: (Moderate) Monitor serum potassium concentration during concomitant drospirenone and potassium-sparing diuretic use due to increased risk for hyperkalemia. Drospirenone has anti-mineralocorticoid activity, including the potential for hyperkalemia.
Drospirenone; Ethinyl Estradiol: (Moderate) Monitor serum potassium concentration during concomitant drospirenone and potassium-sparing diuretic use due to increased risk for hyperkalemia. Drospirenone has anti-mineralocorticoid activity, including the potential for hyperkalemia.
Drospirenone; Ethinyl Estradiol; Levomefolate: (Moderate) Monitor serum potassium concentration during concomitant drospirenone and potassium-sparing diuretic use due to increased risk for hyperkalemia. Drospirenone has anti-mineralocorticoid activity, including the potential for hyperkalemia. (Minor) L-methylfolate and triamterene should be used together cautiously. Plasma concentrations of L-methylfolate may be reduced when used concomitantly with triamterene. Monitor patients for decreased efficacy of L-methylfolate if these agents are used together.
Dulaglutide: (Minor) Triamterene can decrease the hypoglycemic effects of antidiabetic agents, such as incretin mimetics, by producing an increase in blood glucose levels. Patients on antidiabetics should be monitored for changes in blood glucose control if triamterene is added or deleted. Dosage adjustments may be necessary.
Duloxetine: (Moderate) Monitor for signs and symptoms of hyponatremia during concomitant diuretic and serotonin norepinephrine reuptake inhibitor (SNRI) use; consider discontinuing the SNRI if symptomatic hyponatremia occurs and institute appropriate medical intervention. Concomitant use increases the risk for developing hyponatremia.
Empagliflozin: (Moderate) Administer empagliflozin with caution in patients receiving diuretics. When empagliflozin is initiated in patients already receiving diuretics, volume depletion can occur. Patients with impaired renal function, low systolic blood pressure, or who are elderly may also be at a greater risk for volume depletion and perhaps symptomatic hypotension. Before initiating empagliflozin in patients with one or more of these characteristics, assess volume status and correct if necessary. Monitor for signs and symptoms after initiating therapy.
Empagliflozin; Linagliptin: (Moderate) Administer empagliflozin with caution in patients receiving diuretics. When empagliflozin is initiated in patients already receiving diuretics, volume depletion can occur. Patients with impaired renal function, low systolic blood pressure, or who are elderly may also be at a greater risk for volume depletion and perhaps symptomatic hypotension. Before initiating empagliflozin in patients with one or more of these characteristics, assess volume status and correct if necessary. Monitor for signs and symptoms after initiating therapy. (Minor) Thiazide diuretics and triamterene can decrease the hypoglycemic effects of antidiabetic agents by producing an increase in blood glucose concentrations. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, thiazide diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients receiving linagliptin should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary.
Empagliflozin; Linagliptin; Metformin: (Moderate) Administer empagliflozin with caution in patients receiving diuretics. When empagliflozin is initiated in patients already receiving diuretics, volume depletion can occur. Patients with impaired renal function, low systolic blood pressure, or who are elderly may also be at a greater risk for volume depletion and perhaps symptomatic hypotension. Before initiating empagliflozin in patients with one or more of these characteristics, assess volume status and correct if necessary. Monitor for signs and symptoms after initiating therapy. (Minor) Thiazide diuretics and triamterene can decrease the hypoglycemic effects of antidiabetic agents by producing an increase in blood glucose concentrations. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, thiazide diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients receiving linagliptin should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary.
Empagliflozin; Metformin: (Moderate) Administer empagliflozin with caution in patients receiving diuretics. When empagliflozin is initiated in patients already receiving diuretics, volume depletion can occur. Patients with impaired renal function, low systolic blood pressure, or who are elderly may also be at a greater risk for volume depletion and perhaps symptomatic hypotension. Before initiating empagliflozin in patients with one or more of these characteristics, assess volume status and correct if necessary. Monitor for signs and symptoms after initiating therapy.
Enalapril, Enalaprilat: (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.
Enalapril; Hydrochlorothiazide, HCTZ: (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.
Entecavir: (Minor) Both entecavir and triamterene are secreted by active tubular secretion. In theory, coadministration of entecavir with triamterene may increase the serum concentrations of either drug due to competition for the drug elimination pathway. Monitor for adverse effects when these drugs are coadministered.
Ephedrine: (Major) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by potassium-sparing diuretics. 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 may reduce the antihypertensive effects produced by potassium-sparing diuretics. Blood pressure and heart rates should be monitored closely to confirm that the desired antihypertensive effect is achieved.
Epinephrine: (Moderate) Monitor blood pressure and heart rate during concomitant epinephrine and potassium-sparing diuretic use. Potassium-sparing diuretics may antagonize the pressor effects and potentiate the arrhythmogenic effects of epinephrine.
Eplerenone: (Contraindicated) Eplerenone should not be used concomitantly with potassium-sparing diuretics (e.g., amiloride, spironolactone, triamterene) because of the increased risk of developing hyperkalemia. The combine use of these medications in patients with hypertension or renal impairment contraindicated.
Epoprostenol: (Moderate) Epoprostenol can have additive effects when administered with other antihypertensive agents. These effects can be used to therapeutic advantage, but dosage adjustments may be necessary.
Eprosartan: (Moderate) Monitor serum potassium concentrations in patients receiving angiotensin II receptor antagonists concomitantly with triamterene. Concomitant use may result in hyperkalemia.
Eprosartan; Hydrochlorothiazide, HCTZ: (Moderate) Monitor serum potassium concentrations in patients receiving angiotensin II receptor antagonists concomitantly with triamterene. Concomitant use may result in hyperkalemia.
Ertugliflozin; Sitagliptin: (Minor) Triamterene can interfere with the hypoglycemic effects of antidiabetic agents. This can lead to a loss of diabetic control, so diabetic patients should be monitored closely.
Escitalopram: (Moderate) Monitor for signs and symptoms of hyponatremia during concomitant diuretic and escitalopram use; consider discontinuing escitalopram if symptomatic hyponatremia occurs and institute appropriate medical intervention. Concomitant use increases the risk for developing hyponatremia.
Estradiol: (Minor) Estrogens can induce fluid retention and may increase blood pressure in some patients; patients who are receiving antihypertensive agents concurrently with hormone therapy should be monitored for antihypertensive effectiveness.
Ethiodized Oil: (Major) Do not use diuretics before non-ionic contrast media administration. Concomitant use of diuretics and non-ionic contrast media may increase the risk for acute kidney injury, including renal failure.
Etodolac: (Moderate) Nonsteroidal anti-inflammatory drugs (NSAIDs) may reduce the natriuretic effect of diuretics in some patients. NSAIDS have been associated with an inhibition of prostaglandin synthesis, which may result in reduced renal blood flow leading to renal insufficiency and increases in blood pressure that are often accompanied by peripheral edema and weight gain. Patients taking diuretics and NSAIDS concurrently are at higher risk of developing renal insufficiency. If an NSAID and a diuretic are used concurrently, carefully monitor the patient for signs and symptoms of decreased renal function and diuretic efficacy.
Etomidate: (Moderate) General anesthetics can potentiate the hypotensive effects of antihypertensive agents.
Exenatide: (Minor) Triamterene can decrease the hypoglycemic effects of antidiabetic agents, such as incretin mimetics, by producing an increase in blood glucose levels. Patients on antidiabetics should be monitored for changes in blood glucose control if triamterene is added or deleted. Dosage adjustments may be necessary.
Fenoprofen: (Moderate) Nonsteroidal anti-inflammatory drugs (NSAIDs) may reduce the natriuretic effect of diuretics in some patients. NSAIDS have been associated with an inhibition of prostaglandin synthesis, which may result in reduced renal blood flow leading to renal insufficiency and increases in blood pressure that are often accompanied by peripheral edema and weight gain. Patients taking diuretics and NSAIDS concurrently are at higher risk of developing renal insufficiency. If an NSAID and a diuretic are used concurrently, carefully monitor the patient for signs and symptoms of decreased renal function and diuretic efficacy.
Fentanyl: (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of triamterene and fentanyl; increase the dosage of triamterene as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone.
Fexofenadine; Pseudoephedrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine 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.
Finerenone: (Moderate) Monitor serum potassium concentrations closely if finerenone and potassium-sparing diuretics are used together. Concomitant use may increase the risk of hyperkalemia.
Fish Oil, Omega-3 Fatty Acids (Dietary Supplements): (Moderate) Monitor blood pressure during concomitant fish oil and potassium-sparing diuretic use. Concomitant use may result in additive hypotension; high doses of fish oil may produce a blood pressure lowering effect.
Fludrocortisone: (Minor) The manufacturer of spironolactone lists corticosteroids as a potential drug that interacts with spironolactone. Intensified electrolyte depletion, particularly hypokalemia, may occur. However, potassium-sparing diuretics such as spironolactone do not induce hypokalemia. In fact, hypokalemia is one of the indications for potassium-sparing diuretic therapy. Therefore, drugs that induce potassium loss, such as corticosteroids, could counter the hyperkalemic effects of potassium-sparing diuretics.
Flunisolide: (Minor) The manufacturer of spironolactone lists corticosteroids as a potential drug that interacts with spironolactone. Intensified electrolyte depletion, particularly hypokalemia, may occur. However, potassium-sparing diuretics such as spironolactone do not induce hypokalemia. In fact, hypokalemia is one of the indications for potassium-sparing diuretic therapy. Therefore, drugs that induce potassium loss, such as corticosteroids, could counter the hyperkalemic effects of potassium-sparing diuretics.
Fluoxetine: (Moderate) Monitor for signs and symptoms of hyponatremia during concomitant diuretic and fluoxetine use; consider discontinuing fluoxetine if symptomatic hyponatremia occurs and institute appropriate medical intervention. Concomitant use increases the risk for developing hyponatremia.
Flurbiprofen: (Moderate) Nonsteroidal anti-inflammatory drugs (NSAIDs) may reduce the natriuretic effect of diuretics in some patients. NSAIDS have been associated with an inhibition of prostaglandin synthesis, which may result in reduced renal blood flow leading to renal insufficiency and increases in blood pressure that are often accompanied by peripheral edema and weight gain. Patients taking diuretics and NSAIDS concurrently are at higher risk of developing renal insufficiency. If an NSAID and a diuretic are used concurrently, carefully monitor the patient for signs and symptoms of decreased renal function and diuretic efficacy.
Fluticasone: (Minor) The manufacturer of spironolactone lists corticosteroids as a potential drug that interacts with spironolactone. Intensified electrolyte depletion, particularly hypokalemia, may occur. However, potassium-sparing diuretics such as spironolactone do not induce hypokalemia. In fact, hypokalemia is one of the indications for potassium-sparing diuretic therapy. Therefore, drugs that induce potassium loss, such as corticosteroids, could counter the hyperkalemic effects of potassium-sparing diuretics.
Fluticasone; Salmeterol: (Minor) The manufacturer of spironolactone lists corticosteroids as a potential drug that interacts with spironolactone. Intensified electrolyte depletion, particularly hypokalemia, may occur. However, potassium-sparing diuretics such as spironolactone do not induce hypokalemia. In fact, hypokalemia is one of the indications for potassium-sparing diuretic therapy. Therefore, drugs that induce potassium loss, such as corticosteroids, could counter the hyperkalemic effects of potassium-sparing diuretics.
Fluticasone; Umeclidinium; Vilanterol: (Minor) The manufacturer of spironolactone lists corticosteroids as a potential drug that interacts with spironolactone. Intensified electrolyte depletion, particularly hypokalemia, may occur. However, potassium-sparing diuretics such as spironolactone do not induce hypokalemia. In fact, hypokalemia is one of the indications for potassium-sparing diuretic therapy. Therefore, drugs that induce potassium loss, such as corticosteroids, could counter the hyperkalemic effects of potassium-sparing diuretics.
Fluticasone; Vilanterol: (Minor) The manufacturer of spironolactone lists corticosteroids as a potential drug that interacts with spironolactone. Intensified electrolyte depletion, particularly hypokalemia, may occur. However, potassium-sparing diuretics such as spironolactone do not induce hypokalemia. In fact, hypokalemia is one of the indications for potassium-sparing diuretic therapy. Therefore, drugs that induce potassium loss, such as corticosteroids, could counter the hyperkalemic effects of potassium-sparing diuretics.
Fluvoxamine: (Moderate) Patients receiving a diuretic during treatment with fluvoxamine may be at greater risk of developing syndrome of inappropriate antidiuretic hormone secretion (SIADH). Hyponatremia due to SIADH has been reported during therapy with SSRIs. Cases involving serum sodium levels lower than 110 mmol/L have occurred. Hyponatremia may be potentiated by agents which can cause sodium depletion such as diuretics. Discontinuation of fluvoxamine should be considered in patients who develop symptomatic hyponatremia.
Formoterol; Mometasone: (Minor) The manufacturer of spironolactone lists corticosteroids as a potential drug that interacts with spironolactone. Intensified electrolyte depletion, particularly hypokalemia, may occur. However, potassium-sparing diuretics such as spironolactone do not induce hypokalemia. In fact, hypokalemia is one of the indications for potassium-sparing diuretic therapy. Therefore, drugs that induce potassium loss, such as corticosteroids, could counter the hyperkalemic effects of potassium-sparing diuretics.
Fosinopril: (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.
Fosinopril; Hydrochlorothiazide, HCTZ: (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.
General anesthetics: (Moderate) General anesthetics can potentiate the hypotensive effects of antihypertensive agents.
Glimepiride: (Minor) Triamterene can interfere with the hypoglycemic effects of antidiabetic agents. This can lead to a loss of diabetic control, so diabetic patients should be monitored closely.
Glipizide: (Minor) Triamterene can interfere with the hypoglycemic effects of antidiabetic agents. This can lead to a loss of diabetic control, so diabetic patients should be monitored closely.
Glipizide; Metformin: (Minor) Triamterene can interfere with the hypoglycemic effects of antidiabetic agents. This can lead to a loss of diabetic control, so diabetic patients should be monitored closely.
Glyburide: (Minor) Triamterene can interfere with the hypoglycemic effects of antidiabetic agents. This can lead to a loss of diabetic control, so diabetic patients should be monitored closely.
Glyburide; Metformin: (Minor) Triamterene can interfere with the hypoglycemic effects of antidiabetic agents. This can lead to a loss of diabetic control, so diabetic patients should be monitored closely.
Guaifenesin; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
Guaifenesin; Pseudoephedrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine 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.
Haloperidol: (Moderate) In general, haloperidol should be used cautiously with antihypertensive agents due to the possibility of additive hypotension.
Homatropine; Hydrocodone: (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of triamterene and hydrocodone; increase the dosage of triamterene as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone.
Hydralazine; Isosorbide Dinitrate, ISDN: (Moderate) Monitor blood pressure during concomitant potassium-sparing diuretic and nitrate use due to risk for additive hypotension.
Hydrochlorothiazide, HCTZ; Moexipril: (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.
Hydrocodone: (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of triamterene and hydrocodone; increase the dosage of triamterene as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone.
Hydrocodone; Ibuprofen: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant triamterene and ibuprofen use. Nonsteroidal antiinflammatory drugs (NSAIDs) may cause a dose-dependent reduction in renal blood flow, which may precipitate overt renal decompensation, and concomitant diuretic use increases the risk of this reaction. NSAIDs are associated with fluid retention which may blunt the cardiovascular effects of diuretics. (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of triamterene and hydrocodone; increase the dosage of triamterene as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone.
Hydrocortisone: (Minor) The manufacturer of spironolactone lists corticosteroids as a potential drug that interacts with spironolactone. Intensified electrolyte depletion, particularly hypokalemia, may occur. However, potassium-sparing diuretics such as spironolactone do not induce hypokalemia. In fact, hypokalemia is one of the indications for potassium-sparing diuretic therapy. Therefore, drugs that induce potassium loss, such as corticosteroids, could counter the hyperkalemic effects of potassium-sparing diuretics.
Hydromorphone: (Moderate) Monitor for decreased diuretic efficacy and additive orthostatic hypotension when triamterene is administered with hydromorphone. Adjustments to diuretic therapy may be needed in some patients. The efficacy of diuretics may be reduced due to opioid-induced release of antidiuretic hormone.
Hyoscyamine; Methenamine; Methylene Blue; Phenyl Salicylate; Sodium Biphosphate: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant triamterene and salicylate use. Salicylate use decreases glomerular filtration rate and renal blood flow, and concomitant diuretic use may increase the risk of this reaction. Salicylates may diminish the effectiveness of diuretics due to inhibition of renal prostaglandins, leading to decreased renal blood flow and salt and fluid retention.
Ibritumomab Tiuxetan: (Major) Avoid coadministration of potassium phosphate and potassium-sparing diuretics 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. (Major) The use of potassium supplements in patients treated with triamterene is generally contraindicated. Concomitant use may increase the risk of hyperkalemia. If potassium supplementation is used, monitor serum potassium concentrations closely.
Ibuprofen lysine: (Moderate) Ibuprofen lysine may reduce the effect of diuretics; diuretics can increase the risk of nephrotoxicity of NSAIDs in dehydrated patients. During coadministration of NSAIDs and diuretic therapy, patients should be monitored for changes in the effectiveness of their diuretic therapy and for signs and symptoms of renal impairment.
Ibuprofen: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant triamterene and ibuprofen use. Nonsteroidal antiinflammatory drugs (NSAIDs) may cause a dose-dependent reduction in renal blood flow, which may precipitate overt renal decompensation, and concomitant diuretic use increases the risk of this reaction. NSAIDs are associated with fluid retention which may blunt the cardiovascular effects of diuretics.
Ibuprofen; Famotidine: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant triamterene and ibuprofen use. Nonsteroidal antiinflammatory drugs (NSAIDs) may cause a dose-dependent reduction in renal blood flow, which may precipitate overt renal decompensation, and concomitant diuretic use increases the risk of this reaction. NSAIDs are associated with fluid retention which may blunt the cardiovascular effects of diuretics.
Ibuprofen; Oxycodone: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant triamterene and ibuprofen use. Nonsteroidal antiinflammatory drugs (NSAIDs) may cause a dose-dependent reduction in renal blood flow, which may precipitate overt renal decompensation, and concomitant diuretic use increases the risk of this reaction. NSAIDs are associated with fluid retention which may blunt the cardiovascular effects of diuretics. (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of triamterene and oxycodone; increase the dosage of triamterene as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone.
Ibuprofen; Pseudoephedrine: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant triamterene and ibuprofen use. Nonsteroidal antiinflammatory drugs (NSAIDs) may cause a dose-dependent reduction in renal blood flow, which may precipitate overt renal decompensation, and concomitant diuretic use increases the risk of this reaction. NSAIDs are associated with fluid retention which may blunt the cardiovascular effects of diuretics. (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine 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.
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) Amiloride can have additive effects when administered with other antihypertensive agents. These effects can be used to therapeutic advantage, but dosage adjustments may be necessary.
Incretin Mimetics: (Minor) Triamterene can decrease the hypoglycemic effects of antidiabetic agents, such as incretin mimetics, by producing an increase in blood glucose levels. Patients on antidiabetics should be monitored for changes in blood glucose control if triamterene is added or deleted. Dosage adjustments may be necessary.
Indapamide: (Moderate) The effects of indapamide may be additive when administered with other antihypertensive agents or diuretics. This may be desirable, but occasionally orthostatic hypotension may occur. Dosages should be adjusted based on clinical response.
Indomethacin: (Major) Indomethacin and triamterene should not be given together; reversible acute renal failure occurred in 2 of 4 patients who had the addition of triamterene to their maintenance indomethacin regimen. Also, additive effects on serum potassium concentrations may occur with potassium-sparing diuretics and indomethacin usage. In addition, nonsteroidal anti-inflammatory drugs (NSAIDs) may reduce the natriuretic effect of diuretics in some patients. NSAIDS have been associated with an inhibition of prostaglandin synthesis, which may result in reduced renal blood flow leading to renal insufficiency and increases in blood pressure that are often accompanied by peripheral edema and weight gain. Patients taking diuretics and NSAIDS concurrently are at higher risk of developing renal insufficiency. If indomethacin and a diuretic are used concurrently, carefully monitor the patient for signs and symptoms of decreased renal function and diuretic efficacy.
Inotersen: (Moderate) Use caution with concomitant use of inotersen and diuretics due to the risk of glomerulonephritis and nephrotoxicity.
Insulin Aspart: (Minor) Triamterene can decrease the hypoglycemic effects of insulin by producing an increase in blood glucose levels. Patients receiving insulin should be closely monitored for signs indicating loss of diabetic control when therapy with triamterene is instituted. In addition, patients receiving insulin should be closely monitored for signs of hypoglycemia when therapy with any of these other agents is discontinued.
Insulin Aspart; Insulin Aspart Protamine: (Minor) Triamterene can decrease the hypoglycemic effects of insulin by producing an increase in blood glucose levels. Patients receiving insulin should be closely monitored for signs indicating loss of diabetic control when therapy with triamterene is instituted. In addition, patients receiving insulin should be closely monitored for signs of hypoglycemia when therapy with any of these other agents is discontinued.
Insulin Degludec: (Minor) Triamterene can decrease the hypoglycemic effects of insulin by producing an increase in blood glucose levels. Patients receiving insulin should be closely monitored for signs indicating loss of diabetic control when therapy with triamterene is instituted. In addition, patients receiving insulin should be closely monitored for signs of hypoglycemia when therapy with any of these other agents is discontinued.
Insulin Degludec; Liraglutide: (Minor) Triamterene can decrease the hypoglycemic effects of antidiabetic agents, such as incretin mimetics, by producing an increase in blood glucose levels. Patients on antidiabetics should be monitored for changes in blood glucose control if triamterene is added or deleted. Dosage adjustments may be necessary. (Minor) Triamterene can decrease the hypoglycemic effects of insulin by producing an increase in blood glucose levels. Patients receiving insulin should be closely monitored for signs indicating loss of diabetic control when therapy with triamterene is instituted. In addition, patients receiving insulin should be closely monitored for signs of hypoglycemia when therapy with any of these other agents is discontinued.
Insulin Detemir: (Minor) Triamterene can decrease the hypoglycemic effects of insulin by producing an increase in blood glucose levels. Patients receiving insulin should be closely monitored for signs indicating loss of diabetic control when therapy with triamterene is instituted. In addition, patients receiving insulin should be closely monitored for signs of hypoglycemia when therapy with any of these other agents is discontinued.
Insulin Glargine: (Minor) Triamterene can decrease the hypoglycemic effects of insulin by producing an increase in blood glucose levels. Patients receiving insulin should be closely monitored for signs indicating loss of diabetic control when therapy with triamterene is instituted. In addition, patients receiving insulin should be closely monitored for signs of hypoglycemia when therapy with any of these other agents is discontinued.
Insulin Glargine; Lixisenatide: (Minor) Triamterene can decrease the hypoglycemic effects of antidiabetic agents, such as incretin mimetics, by producing an increase in blood glucose levels. Patients on antidiabetics should be monitored for changes in blood glucose control if triamterene is added or deleted. Dosage adjustments may be necessary. (Minor) Triamterene can decrease the hypoglycemic effects of insulin by producing an increase in blood glucose levels. Patients receiving insulin should be closely monitored for signs indicating loss of diabetic control when therapy with triamterene is instituted. In addition, patients receiving insulin should be closely monitored for signs of hypoglycemia when therapy with any of these other agents is discontinued.
Insulin Glulisine: (Minor) Triamterene can decrease the hypoglycemic effects of insulin by producing an increase in blood glucose levels. Patients receiving insulin should be closely monitored for signs indicating loss of diabetic control when therapy with triamterene is instituted. In addition, patients receiving insulin should be closely monitored for signs of hypoglycemia when therapy with any of these other agents is discontinued.
Insulin Lispro: (Minor) Triamterene can decrease the hypoglycemic effects of insulin by producing an increase in blood glucose levels. Patients receiving insulin should be closely monitored for signs indicating loss of diabetic control when therapy with triamterene is instituted. In addition, patients receiving insulin should be closely monitored for signs of hypoglycemia when therapy with any of these other agents is discontinued.
Insulin Lispro; Insulin Lispro Protamine: (Minor) Triamterene can decrease the hypoglycemic effects of insulin by producing an increase in blood glucose levels. Patients receiving insulin should be closely monitored for signs indicating loss of diabetic control when therapy with triamterene is instituted. In addition, patients receiving insulin should be closely monitored for signs of hypoglycemia when therapy with any of these other agents is discontinued.
Insulin, Inhaled: (Minor) Triamterene can decrease the hypoglycemic effects of insulin by producing an increase in blood glucose levels. Patients receiving insulin should be closely monitored for signs indicating loss of diabetic control when therapy with triamterene is instituted. In addition, patients receiving insulin should be closely monitored for signs of hypoglycemia when therapy with any of these other agents is discontinued.
Insulins: (Minor) Triamterene can decrease the hypoglycemic effects of insulin by producing an increase in blood glucose levels. Patients receiving insulin should be closely monitored for signs indicating loss of diabetic control when therapy with triamterene is instituted. In addition, patients receiving insulin should be closely monitored for signs of hypoglycemia when therapy with any of these other agents is discontinued.
Intravenous Lipid Emulsions: (Moderate) Monitor blood pressure during concomitant fish oil and potassium-sparing diuretic use. Concomitant use may result in additive hypotension; high doses of fish oil may produce a blood pressure lowering effect.
Iodine; Potassium Iodide, KI: (Major) The use of potassium supplements in patients treated with triamterene is generally contraindicated. Concomitant use may increase the risk of hyperkalemia. If potassium supplementation is used, monitor serum potassium concentrations closely.
Iodixanol: (Major) Do not use diuretics before non-ionic contrast media administration. Concomitant use of diuretics and non-ionic contrast media may increase the risk for acute kidney injury, including renal failure.
Iohexol: (Major) Do not use diuretics before non-ionic contrast media administration. Concomitant use of diuretics and non-ionic contrast media may increase the risk for acute kidney injury, including renal failure.
Iomeprol: (Major) Do not use diuretics before non-ionic contrast media administration. Concomitant use of diuretics and non-ionic contrast media may increase the risk for acute kidney injury, including renal failure.
Iopamidol: (Major) Do not use diuretics before non-ionic contrast media administration. Concomitant use of diuretics and non-ionic contrast media may increase the risk for acute kidney injury, including renal failure.
Iopromide: (Major) Do not use diuretics before non-ionic contrast media administration. Concomitant use of diuretics and non-ionic contrast media may increase the risk for acute kidney injury, including renal failure.
Ioversol: (Major) Do not use diuretics before non-ionic contrast media administration. Concomitant use of diuretics and non-ionic contrast media may increase the risk for acute kidney injury, including renal failure.
Irbesartan: (Moderate) Monitor serum potassium concentrations in patients receiving angiotensin II receptor antagonists concomitantly with triamterene. Concomitant use may result in hyperkalemia.
Irbesartan; Hydrochlorothiazide, HCTZ: (Moderate) Monitor serum potassium concentrations in patients receiving angiotensin II receptor antagonists concomitantly with triamterene. Concomitant use may result in hyperkalemia.
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 diuretics. 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): (Minor) Triamterene can decrease the hypoglycemic effects of insulin by producing an increase in blood glucose levels. Patients receiving insulin should be closely monitored for signs indicating loss of diabetic control when therapy with triamterene is instituted. In addition, patients receiving insulin should be closely monitored for signs of hypoglycemia when therapy with any of these other agents is discontinued.
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) Monitor blood pressure during concomitant potassium-sparing diuretic and nitrate use due to risk for additive hypotension.
Isosorbide Mononitrate: (Moderate) Monitor blood pressure during concomitant potassium-sparing diuretic and nitrate use due to risk for additive hypotension.
Isosulfan Blue: (Major) Do not use diuretics before non-ionic contrast media administration. Concomitant use of diuretics and non-ionic contrast media may increase the risk for acute kidney injury, including renal failure.
Ketamine: (Moderate) General anesthetics can potentiate the hypotensive effects of antihypertensive agents.
Ketoprofen: (Moderate) Nonsteroidal anti-inflammatory drugs (NSAIDs) may reduce the natriuretic effect of diuretics in some patients. NSAIDS have been associated with an inhibition of prostaglandin synthesis, which may result in reduced renal blood flow leading to renal insufficiency and increases in blood pressure that are often accompanied by peripheral edema and weight gain. Patients taking diuretics and NSAIDS concurrently are at higher risk of developing renal insufficiency. If an NSAID and a diuretic are used concurrently, carefully monitor the patient for signs and symptoms of decreased renal function and diuretic efficacy.
Ketorolac: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant triamterene and ketorolac use. Nonsteroidal antiinflammatory drugs (NSAIDs) may cause a dose-dependent reduction in renal blood flow, which may precipitate overt renal decompensation, and concomitant diuretic use increases the risk of this reaction. NSAIDs are associated with fluid retention which may blunt the cardiovascular effects of diuretics.
Levodopa: (Moderate) Monitor blood pressure during concomitant levodopa and potassium-sparing diuretic use due to risk for additive hypotension; a potassium-sparing diuretic dosage adjustment may be necessary. Symptomatic postural hypotension has occurred when carbidopa; levodopa was added in a person receiving antihypertensive drugs.
Levomefolate: (Minor) L-methylfolate and triamterene should be used together cautiously. Plasma concentrations of L-methylfolate may be reduced when used concomitantly with triamterene. Monitor patients for decreased efficacy of L-methylfolate if these agents are used together.
Levomilnacipran: (Moderate) Monitor for signs and symptoms of hyponatremia during concomitant diuretic and serotonin norepinephrine reuptake inhibitor (SNRI) use; consider discontinuing the SNRI if symptomatic hyponatremia occurs and institute appropriate medical intervention. Concomitant use increases the risk for developing hyponatremia.
Levorphanol: (Moderate) Monitor for decreased diuretic efficacy and additive orthostatic hypotension when triamterene is administered with levorphanol. Adjustments to diuretic therapy may be needed in some patients. The efficacy of diuretics may be reduced due to opioid-induced release of antidiuretic hormone.
Lidocaine; Epinephrine: (Moderate) Monitor blood pressure and heart rate during concomitant epinephrine and potassium-sparing diuretic use. Potassium-sparing diuretics may antagonize the pressor effects and potentiate the arrhythmogenic effects of epinephrine.
Linagliptin: (Minor) Thiazide diuretics and triamterene can decrease the hypoglycemic effects of antidiabetic agents by producing an increase in blood glucose concentrations. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, thiazide diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients receiving linagliptin should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary.
Linagliptin; Metformin: (Minor) Thiazide diuretics and triamterene can decrease the hypoglycemic effects of antidiabetic agents by producing an increase in blood glucose concentrations. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, thiazide diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients receiving linagliptin should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary.
Liraglutide: (Minor) Triamterene can decrease the hypoglycemic effects of antidiabetic agents, such as incretin mimetics, by producing an increase in blood glucose levels. Patients on antidiabetics should be monitored for changes in blood glucose control if triamterene is added or deleted. Dosage adjustments may be necessary.
Lisdexamfetamine: (Minor) Lisedexamfetamine may increase both systolic and diastolic blood pressure and may counteract the activity of some antihypertensive agents, like potassium-sparing diuretics. Close monitoring of blood pressure is advised.
Lisinopril: (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.
Lisinopril; Hydrochlorothiazide, HCTZ: (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.
Lithium: (Minor) The risk of lithium toxicity may be increased in patients receiving medications that affect kidney function and sodium excretion, such as diuretics. However, concurrent use of potassium-sparing diuretics (e.g., amiloride, spironolactone, triamterene) with lithium is generally regarded as safe. Lithium is primarily reabsorbed from the proximal tubules whereas potassium-sparing diuretics inhibit the endothelial sodium channel in the renal collecting duct thereby inhibiting reabsorption of sodium and lithium. In one small study evaluating concurrent use of lithium and spironolactone, lithium clearance was increased by 16%, which was not considered clinically significant. Amiloride has been safely used as a reversal agent for lithium-induced nephrogenic diabetes insipidus. There is a lack of evidence to evaluate the effect of lithium and triamterene co-administration, however, a significant interaction would not be expected due to the pharmacologic similarities with other potassium-sparing diuretics.
Lixisenatide: (Minor) Triamterene can decrease the hypoglycemic effects of antidiabetic agents, such as incretin mimetics, by producing an increase in blood glucose levels. Patients on antidiabetics should be monitored for changes in blood glucose control if triamterene is added or deleted. Dosage adjustments may be necessary.
Loratadine; Pseudoephedrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine 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.
Losartan: (Moderate) Monitor serum potassium concentrations in patients receiving angiotensin II receptor antagonists concomitantly with triamterene. Concomitant use may result in hyperkalemia.
Losartan; Hydrochlorothiazide, HCTZ: (Moderate) Monitor serum potassium concentrations in patients receiving angiotensin II receptor antagonists concomitantly with triamterene. Concomitant use may result in hyperkalemia.
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 Salicylate: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant triamterene and salicylate use. Salicylate use decreases glomerular filtration rate and renal blood flow, and concomitant diuretic use may increase the risk of this reaction. Salicylates may diminish the effectiveness of diuretics due to inhibition of renal prostaglandins, leading to decreased renal blood flow and salt and fluid retention.
Magnesium Sulfate; Potassium Sulfate; Sodium Sulfate: (Moderate) Use caution when prescribing sulfate salt bowel preparation in patients taking concomitant medications that may affect renal function such as diuretics.
Mannitol: (Major) Avoid use of other diuretics with mannitol, if possible. Concomitant administration may potentiate the renal toxicity of mannitol.
Meclofenamate Sodium: (Moderate) Nonsteroidal anti-inflammatory drugs (NSAIDs) may reduce the natriuretic effect of diuretics in some patients. NSAIDS have been associated with an inhibition of prostaglandin synthesis, which may result in reduced renal blood flow leading to renal insufficiency and increases in blood pressure that are often accompanied by peripheral edema and weight gain. Patients taking diuretics and NSAIDS concurrently are at higher risk of developing renal insufficiency. If an NSAID and a diuretic are used concurrently, carefully monitor the patient for signs and symptoms of decreased renal function and diuretic efficacy.
Mefenamic Acid: (Moderate) Nonsteroidal anti-inflammatory drugs (NSAIDs) may reduce the natriuretic effect of diuretics in some patients. NSAIDS have been associated with an inhibition of prostaglandin synthesis, which may result in reduced renal blood flow leading to renal insufficiency and increases in blood pressure that are often accompanied by peripheral edema and weight gain. Patients taking diuretics and NSAIDS concurrently are at higher risk of developing renal insufficiency. If an NSAID and a diuretic are used concurrently, carefully monitor the patient for signs and symptoms of decreased renal function and diuretic efficacy.
Meloxicam: (Moderate) Nonsteroidal anti-inflammatory drugs (NSAIDs) may reduce the natriuretic effect of diuretics in some patients. NSAIDS have been associated with an inhibition of prostaglandin synthesis, which may result in reduced renal blood flow leading to renal insufficiency and increases in blood pressure that are often accompanied by peripheral edema and weight gain. Patients taking diuretics and NSAIDS concurrently are at higher risk of developing renal insufficiency. If an NSAID and a diuretic are used concurrently, carefully monitor the patient for signs and symptoms of decreased renal function and diuretic efficacy.
Memantine: (Minor) Memantine is excreted in part by renal tubular secretion. Competition of memantine for excretion with other drugs that are also eliminated by tubular secretion, such as triamterene, could result in elevated serum concentrations of one or both drugs.
Meperidine: (Moderate) Monitor for decreased diuretic efficacy and additive orthostatic hypotension when triamterene is administered with meperidine. Adjustments to diuretic therapy may be needed in some patients. The efficacy of diuretics may be reduced due to opioid-induced release of antidiuretic hormone.
Metformin; Saxagliptin: (Minor) Triamterene can interfere with the hypoglycemic effects of antidiabetic agents. This can lead to a loss of diabetic control, so diabetic patients should be monitored closely.
Metformin; Sitagliptin: (Minor) Triamterene can interfere with the hypoglycemic effects of antidiabetic agents. This can lead to a loss of diabetic control, so diabetic patients should be monitored closely.
Methadone: (Moderate) Monitor for decreased diuretic efficacy and additive orthostatic hypotension when triamterene is administered with methadone. Adjustments to diuretic therapy may be needed in some patients. The efficacy of diuretics may be reduced due to opioid-induced release of antidiuretic hormone.
Methamphetamine: (Minor) Amphetamines increase both systolic and diastolic blood pressure and may counteract the activity of some antihypertensive agents, like potassium-sparing diuretics. Close monitoring of blood pressure is advised.
Methazolamide: (Moderate) Carbonic anhydrase inhibitors promote electrolyte excretion including hydrogen ions, sodium, and potassium. They can enhance the sodium depleting effects of other diuretics when used concurrently. Pre-existing hypokalemia and hyperuricemia can also be potentiated by carbonic anhydrase inhibitors. Monitor serum potassium to determine the need for potassium supplementation and alteration in drug therapy.
Methenamine; Sodium Salicylate: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant triamterene and salicylate use. Salicylate use decreases glomerular filtration rate and renal blood flow, and concomitant diuretic use may increase the risk of this reaction. Salicylates may diminish the effectiveness of diuretics due to inhibition of renal prostaglandins, leading to decreased renal blood flow and salt and fluid retention.
Methohexital: (Moderate) Concurrent use of methohexital and antihypertensive agents increases the risk of developing hypotension.
Methylphenidate Derivatives: (Moderate) Monitor blood pressure during concomitant potassium-sparing diuretic and methylphenidate use; a potassium-sparing diuretic dose adjustment may be necessary. Methylphenidate may decrease the effectiveness of medications used to treat hypertension.
Methylphenidate: (Moderate) Monitor blood pressure during concomitant potassium-sparing diuretic and methylphenidate use; a potassium-sparing diuretic dose adjustment may be necessary. Methylphenidate may decrease the effectiveness of medications used to treat hypertension.
Methylprednisolone: (Minor) The manufacturer of spironolactone lists corticosteroids as a potential drug that interacts with spironolactone. Intensified electrolyte depletion, particularly hypokalemia, may occur. However, potassium-sparing diuretics such as spironolactone do not induce hypokalemia. In fact, hypokalemia is one of the indications for potassium-sparing diuretic therapy. Therefore, drugs that induce potassium loss, such as corticosteroids, could counter the hyperkalemic effects of potassium-sparing diuretics.
Midodrine: (Minor) Although the exact mechanism is uncertain, midodrine may be excreted by the same base-secreting pathway of the kidneys responsible for secretion of other basic drugs like triamterene. By this pathway, midodrine may potentially interact with triamterene; however, no drug interactions of this kind have been reported.
Miglitol: (Minor) Triamterene can interfere with the hypoglycemic effects of antidiabetic agents. This can lead to a loss of diabetic control, so diabetic patients should be monitored closely.
Milnacipran: (Moderate) Monitor for signs and symptoms of hyponatremia during concomitant diuretic and serotonin norepinephrine reuptake inhibitor (SNRI) use; consider discontinuing the SNRI if symptomatic hyponatremia occurs and institute appropriate medical intervention. Concomitant use increases the risk for developing hyponatremia.
Milrinone: (Moderate) Concurrent administration of antihypertensive agents could lead to additive hypotension when administered with milrinone. Titrate milrinone dosage according to hemodynamic response.
Mirtazapine: (Moderate) Monitor for signs and symptoms of hyponatremia during concomitant diuretic and mirtazapine use; consider discontinuing mirtazapine if symptomatic hyponatremia occurs and institute appropriate medical intervention. Concomitant use increases the risk for developing hyponatremia.
Moexipril: (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.
Mometasone: (Minor) The manufacturer of spironolactone lists corticosteroids as a potential drug that interacts with spironolactone. Intensified electrolyte depletion, particularly hypokalemia, may occur. However, potassium-sparing diuretics such as spironolactone do not induce hypokalemia. In fact, hypokalemia is one of the indications for potassium-sparing diuretic therapy. Therefore, drugs that induce potassium loss, such as corticosteroids, could counter the hyperkalemic effects of potassium-sparing diuretics.
Morphine: (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of a potassium-sparing diuretic and morphine; increase the dosage of the potassium-sparing diuretic as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone.
Morphine; Naltrexone: (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of a potassium-sparing diuretic and morphine; increase the dosage of the potassium-sparing diuretic as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone.
Nabumetone: (Moderate) Nonsteroidal anti-inflammatory drugs (NSAIDs) may reduce the natriuretic effect of diuretics in some patients. NSAIDS have been associated with an inhibition of prostaglandin synthesis, which may result in reduced renal blood flow leading to renal insufficiency and increases in blood pressure that are often accompanied by peripheral edema and weight gain. Patients taking diuretics and NSAIDS concurrently are at higher risk of developing renal insufficiency. If an NSAID and a diuretic are used concurrently, carefully monitor the patient for signs and symptoms of decreased renal function and diuretic efficacy.
Naproxen: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant triamterene and naproxen use. Nonsteroidal antiinflammatory drugs (NSAIDs) may cause a dose-dependent reduction in renal blood flow, which may precipitate overt renal decompensation, and concomitant diuretic use increases the risk of this reaction. NSAIDs are associated with fluid retention which may blunt the cardiovascular effects of diuretics.
Naproxen; Esomeprazole: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant triamterene and naproxen use. Nonsteroidal antiinflammatory drugs (NSAIDs) may cause a dose-dependent reduction in renal blood flow, which may precipitate overt renal decompensation, and concomitant diuretic use increases the risk of this reaction. NSAIDs are associated with fluid retention which may blunt the cardiovascular effects of diuretics.
Naproxen; Pseudoephedrine: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant triamterene and naproxen use. Nonsteroidal antiinflammatory drugs (NSAIDs) may cause a dose-dependent reduction in renal blood flow, which may precipitate overt renal decompensation, and concomitant diuretic use increases the risk of this reaction. NSAIDs are associated with fluid retention which may blunt the cardiovascular effects of diuretics. (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine 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.
Nebivolol; Valsartan: (Moderate) Monitor serum potassium concentrations in patients receiving angiotensin II receptor antagonists concomitantly with triamterene. Concomitant use may result in hyperkalemia.
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) Monitor blood pressure during concomitant potassium-sparing diuretic and nitrate use due to risk for additive hypotension.
Nitroglycerin: (Moderate) Monitor blood pressure during concomitant potassium-sparing diuretic and nitrate use due to risk for additive hypotension.
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: (Major) Do not use diuretics before non-ionic contrast media administration. Concomitant use of diuretics and non-ionic contrast media may increase the risk for acute kidney injury, including renal failure.
Octreotide: (Moderate) Patients receiving diuretics or other agents to control fluid and electrolyte balance may require dosage adjustments while receiving octreotide due to additive effects.
Olanzapine: (Moderate) Olanzapine may induce orthostatic hypotension and thus enhance the effects of antihypertensive agents.
Olanzapine; Fluoxetine: (Moderate) Monitor for signs and symptoms of hyponatremia during concomitant diuretic and fluoxetine use; consider discontinuing fluoxetine if symptomatic hyponatremia occurs and institute appropriate medical intervention. Concomitant use increases the risk for developing hyponatremia. (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.
Oliceridine: (Moderate) Monitor patients for signs of diminished diuresis and/or effects on blood pressure if diuretics are used concomitantly with oliceridine; increase the dosage of the diuretic as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone.
Olmesartan: (Moderate) Monitor serum potassium concentrations in patients receiving angiotensin II receptor antagonists concomitantly with triamterene. Concomitant use may result in hyperkalemia.
Olmesartan; Amlodipine; Hydrochlorothiazide, HCTZ: (Moderate) Monitor serum potassium concentrations in patients receiving angiotensin II receptor antagonists concomitantly with triamterene. Concomitant use may result in hyperkalemia.
Olmesartan; Hydrochlorothiazide, HCTZ: (Moderate) Monitor serum potassium concentrations in patients receiving angiotensin II receptor antagonists concomitantly with triamterene. Concomitant use may result in hyperkalemia.
Olopatadine; Mometasone: (Minor) The manufacturer of spironolactone lists corticosteroids as a potential drug that interacts with spironolactone. Intensified electrolyte depletion, particularly hypokalemia, may occur. However, potassium-sparing diuretics such as spironolactone do not induce hypokalemia. In fact, hypokalemia is one of the indications for potassium-sparing diuretic therapy. Therefore, drugs that induce potassium loss, such as corticosteroids, could counter the hyperkalemic effects of potassium-sparing diuretics.
Oxaprozin: (Moderate) Nonsteroidal anti-inflammatory drugs (NSAIDs) may reduce the natriuretic effect of diuretics in some patients. NSAIDS have been associated with an inhibition of prostaglandin synthesis, which may result in reduced renal blood flow leading to renal insufficiency and increases in blood pressure that are often accompanied by peripheral edema and weight gain. Patients taking diuretics and NSAIDS concurrently are at higher risk of developing renal insufficiency. If an NSAID and a diuretic are used concurrently, carefully monitor the patient for signs and symptoms of decreased renal function and diuretic efficacy.
Oxybutynin: (Minor) Diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Oxycodone: (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of triamterene and oxycodone; increase the dosage of triamterene as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone.
Oxymetazoline: (Major) The vasoconstricting actions of oxymetazoline, an alpha adrenergic agonist, may reduce the antihypertensive effects produced by diuretics. If these drugs are used together, closely monitor for changes in blood pressure.
Oxymorphone: (Moderate) Monitor for decreased diuretic efficacy and additive orthostatic hypotension when potassium-sparring diuretics are administered with oxymorphone. Adjustments to diuretic therapy may be needed in some patients. The efficacy of diuretics may be reduced due to opioid-induced release of antidiuretic hormone.
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 potassium-sparing diuretics who are susceptible to hypotension.
Paroxetine: (Moderate) Monitor for signs and symptoms of hyponatremia during concomitant diuretic and paroxetine use; consider discontinuing paroxetine if symptomatic hyponatremia occurs and institute appropriate medical intervention. Concomitant use increases the risk for developing hyponatremia.
Peginterferon Alfa-2b: (Minor) Monitor for adverse effects associated with increased exposure to triamterene if peginterferon alfa-2b is coadministered. Peginterferon alfa-2b is a CYP1A2 inhibitor, while triamterene is a CYP1A2 substrate.
Penicillin G: (Major) Concomitant use of high doses of parenteral penicillin G potassium with potassium-sparing diuretics can cause hyperkalemia.
Pentazocine; Naloxone: (Moderate) Monitor for decreased diuretic efficacy and additive orthostatic hypotension when potassium-sparring diuretics are administered with pentazocine. Adjustments to diuretic therapy may be needed in some patients. The efficacy of diuretics may be reduced due to opioid-induced release of antidiuretic hormone.
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.
Perindopril: (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.
Perindopril; Amlodipine: (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.
Phenelzine: (Moderate) Monitor blood pressure during concomitant potassium-sparing diuretic and phenelzine use due to risk for additive hypotension.
Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
Pioglitazone: (Minor) Triamterene can interfere with the hypoglycemic effects of antidiabetic agents. This can lead to a loss of diabetic control, so diabetic patients should be monitored closely.
Pioglitazone; Glimepiride: (Minor) Triamterene can interfere with the hypoglycemic effects of antidiabetic agents. This can lead to a loss of diabetic control, so diabetic patients should be monitored closely.
Pioglitazone; Metformin: (Minor) Triamterene can interfere with the hypoglycemic effects of antidiabetic agents. This can lead to a loss of diabetic control, so diabetic patients should be monitored closely.
Piroxicam: (Moderate) Nonsteroidal anti-inflammatory drugs (NSAIDs) may reduce the natriuretic effect of diuretics in some patients. NSAIDS have been associated with an inhibition of prostaglandin synthesis, which may result in reduced renal blood flow leading to renal insufficiency and increases in blood pressure that are often accompanied by peripheral edema and weight gain. Patients taking diuretics and NSAIDS concurrently are at higher risk of developing renal insufficiency. If an NSAID and a diuretic are used concurrently, carefully monitor the patient for signs and symptoms of decreased renal function and diuretic efficacy.
Polyethylene Glycol; Electrolytes: (Moderate) Use caution when prescribing sulfate salt bowel preparation in patients taking concomitant medications that may affect renal function such as diuretics.
Polyethylene Glycol; Electrolytes; Ascorbic Acid: (Moderate) Use caution when prescribing sulfate salt bowel preparation in patients taking concomitant medications that may affect renal function such as diuretics.
Potassium Acetate: (Major) The use of potassium supplements in patients treated with triamterene is generally contraindicated. Concomitant use may increase the risk of hyperkalemia. If potassium supplementation is used, monitor serum potassium concentrations closely.
Potassium Bicarbonate: (Major) The use of potassium supplements in patients treated with triamterene is generally contraindicated. Concomitant use may increase the risk of hyperkalemia. If potassium supplementation is used, monitor serum potassium concentrations closely.
Potassium Chloride: (Major) The use of potassium supplements in patients treated with triamterene is generally contraindicated. Concomitant use may increase the risk of hyperkalemia. If potassium supplementation is used, monitor serum potassium concentrations closely.
Potassium Citrate: (Major) The use of potassium supplements in patients treated with triamterene is generally contraindicated. Concomitant use may increase the risk of hyperkalemia. If potassium supplementation is used, monitor serum potassium concentrations closely.
Potassium Citrate; Citric Acid: (Major) The use of potassium supplements in patients treated with triamterene is generally contraindicated. Concomitant use may increase the risk of hyperkalemia. If potassium supplementation is used, monitor serum potassium concentrations closely.
Potassium Gluconate: (Major) The use of potassium supplements in patients treated with triamterene is generally contraindicated. Concomitant use may increase the risk of hyperkalemia. If potassium supplementation is used, monitor serum potassium concentrations closely.
Potassium Iodide, KI: (Major) The use of potassium supplements in patients treated with triamterene is generally contraindicated. Concomitant use may increase the risk of hyperkalemia. If potassium supplementation is used, monitor serum potassium concentrations closely.
Potassium Phosphate: (Major) Avoid coadministration of potassium phosphate and potassium-sparing diuretics 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 potassium-sparing diuretics 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: (Major) The use of potassium supplements in patients treated with triamterene is generally contraindicated. Concomitant use may increase the risk of hyperkalemia. If potassium supplementation is used, monitor serum potassium concentrations closely.
Pramlintide: (Minor) Triamterene can interfere with the hypoglycemic effects of pramlinitide. This can lead to a loss of diabetic control, so diabetic patients should be monitored closely.
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.
Prednisolone: (Minor) The manufacturer of spironolactone lists corticosteroids as a potential drug that interacts with spironolactone. Intensified electrolyte depletion, particularly hypokalemia, may occur. However, potassium-sparing diuretics such as spironolactone do not induce hypokalemia. In fact, hypokalemia is one of the indications for potassium-sparing diuretic therapy. Therefore, drugs that induce potassium loss, such as corticosteroids, could counter the hyperkalemic effects of potassium-sparing diuretics.
Prednisone: (Minor) The manufacturer of spironolactone lists corticosteroids as a potential drug that interacts with spironolactone. Intensified electrolyte depletion, particularly hypokalemia, may occur. However, potassium-sparing diuretics such as spironolactone do not induce hypokalemia. In fact, hypokalemia is one of the indications for potassium-sparing diuretic therapy. Therefore, drugs that induce potassium loss, such as corticosteroids, could counter the hyperkalemic effects of potassium-sparing diuretics.
Prilocaine; Epinephrine: (Moderate) Monitor blood pressure and heart rate during concomitant epinephrine and potassium-sparing diuretic use. Potassium-sparing diuretics may antagonize the pressor effects and potentiate the arrhythmogenic effects of epinephrine.
Probenecid: (Moderate) Probenecid has uricosuric actions. Triamterene can also cause hyperuricemia. Although this effect represents a pharmacodynamic interaction, dosage adjustments of probenecid may be necessary if triamterene is administered to patients being treated with probenecid.
Probenecid; Colchicine: (Moderate) Probenecid has uricosuric actions. Triamterene can also cause hyperuricemia. Although this effect represents a pharmacodynamic interaction, dosage adjustments of probenecid may be necessary if triamterene is administered to patients being treated with probenecid.
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 diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
Propofol: (Moderate) General anesthetics can potentiate the hypotensive effects of antihypertensive agents.
Pseudoephedrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine 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.
Pseudoephedrine; Triprolidine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine 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.
Quinapril: (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.
Quinapril; Hydrochlorothiazide, HCTZ: (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.
Quinidine: (Moderate) Quinidine can decrease blood pressure and should be used cautiously in patients receiving antihypertensive agents due to the potential for additive hypotension.
Ramipril: (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.
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 diuretics. 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: (Minor) Triamterene can decrease the hypoglycemic effects of insulin by producing an increase in blood glucose levels. Patients receiving insulin should be closely monitored for signs indicating loss of diabetic control when therapy with triamterene is instituted. In addition, patients receiving insulin should be closely monitored for signs of hypoglycemia when therapy with any of these other agents is discontinued.
Regular Insulin; Isophane Insulin (NPH): (Minor) Triamterene can decrease the hypoglycemic effects of insulin by producing an increase in blood glucose levels. Patients receiving insulin should be closely monitored for signs indicating loss of diabetic control when therapy with triamterene is instituted. In addition, patients receiving insulin should be closely monitored for signs of hypoglycemia when therapy with any of these other agents is discontinued.
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: (Minor) Triamterene can interfere with the hypoglycemic effects of antidiabetic agents. This can lead to a loss of diabetic control, so diabetic patients should be monitored closely.
Sacubitril; Valsartan: (Moderate) Monitor serum potassium concentrations in patients receiving angiotensin II receptor antagonists concomitantly with triamterene. Concomitant use may result in hyperkalemia.
Salicylates: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant triamterene and salicylate use. Salicylate use decreases glomerular filtration rate and renal blood flow, and concomitant diuretic use may increase the risk of this reaction. Salicylates may diminish the effectiveness of diuretics due to inhibition of renal prostaglandins, leading to decreased renal blood flow and salt and fluid retention.
Salsalate: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant triamterene and salicylate use. Salicylate use decreases glomerular filtration rate and renal blood flow, and concomitant diuretic use may increase the risk of this reaction. Salicylates may diminish the effectiveness of diuretics due to inhibition of renal prostaglandins, leading to decreased renal blood flow and salt and fluid retention.
Saxagliptin: (Minor) Triamterene can interfere with the hypoglycemic effects of antidiabetic agents. This can lead to a loss of diabetic control, so diabetic patients should be monitored closely.
Semaglutide: (Minor) Triamterene can decrease the hypoglycemic effects of antidiabetic agents, such as incretin mimetics, by producing an increase in blood glucose levels. Patients on antidiabetics should be monitored for changes in blood glucose control if triamterene is added or deleted. Dosage adjustments may be necessary.
Serdexmethylphenidate; Dexmethylphenidate: (Moderate) Monitor blood pressure during concomitant potassium-sparing diuretic and methylphenidate use; a potassium-sparing diuretic dose adjustment may be necessary. Methylphenidate may decrease the effectiveness of medications used to treat hypertension.
Serotonin norepinephrine reuptake inhibitors: (Moderate) Monitor for signs and symptoms of hyponatremia during concomitant diuretic and serotonin norepinephrine reuptake inhibitor (SNRI) use; consider discontinuing the SNRI if symptomatic hyponatremia occurs and institute appropriate medical intervention. Concomitant use increases the risk for developing hyponatremia.
Sertraline: (Moderate) Monitor for signs and symptoms of hyponatremia during concomitant diuretic and sertraline use; consider discontinuing sertraline if symptomatic hyponatremia occurs and institute appropriate medical intervention. Concomitant use increases the risk for developing hyponatremia.
Sevoflurane: (Moderate) General anesthetics can potentiate the hypotensive effects of antihypertensive agents.
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.
Sitagliptin: (Minor) Triamterene can interfere with the hypoglycemic effects of antidiabetic agents. This can lead to a loss of diabetic control, so diabetic patients should be monitored closely.
Sodium Phosphate Monobasic Monohydrate; Sodium Phosphate Dibasic Anhydrous: (Moderate) Concomitant use of medicines with potential to alter renal perfusion or function such as diuretics may increase the risk of acute phosphate nephropathy in patients receiving 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 diuretics. In addition, use caution in patients receiving drugs where hypokalemia is a particular risk.
Sodium Sulfate; Magnesium Sulfate; Potassium Chloride: (Major) The use of potassium supplements in patients treated with triamterene is generally contraindicated. Concomitant use may increase the risk of hyperkalemia. If potassium supplementation is used, monitor serum potassium concentrations closely.
Solifenacin: (Minor) Diuretics can increase urinary frequency, which may aggravate bladder symptoms. Risk versus benefit should be addressed in patients receiving diuretics and solifenacin.
Sparsentan: (Moderate) Monitor potassium during concomitant use of sparsentan and potassium-sparing diuretics. Concomitant use increases the risk for hyperkalemia.
Streptozocin: (Minor) Because streptozocin is nephrotoxic, concurrent or subsequent administration of other nephrotoxic agents (e.g., aminoglycosides, amphotericin B, cisplatin, foscarnet, or diuretics) could exacerbate the renal insult.
Sufentanil: (Moderate) Monitor for decreased diuretic efficacy and additive orthostatic hypotension when triamterene is administered with sufentanil. Adjustments to diuretic therapy may be needed in some patients. The efficacy of diuretics may be reduced due to opioid-induced release of antidiuretic hormone.
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: (Major) Avoid use of other folate antagonists, such as triamterene, with sulfamethoxazole; trimethoprim as an increased risk of megaloblastic anemia may occur due to folate deficiency. (Moderate) Monitor serum potassium concentrations if trimethoprim and a potassium-sparing diuretic are used together. Concomitant use may increase the risk of hyperkalemia. The risk for trimethoprim-associated hyperkalemia is greatest in patients with additional risk factors for hyperkalemia such as age greater than 65 years, those with underlying disorders of potassium metabolism, renal insufficiency, or those requiring high doses of trimethoprim.
Sulfonylureas: (Minor) Triamterene can interfere with the hypoglycemic effects of antidiabetic agents. This can lead to a loss of diabetic control, so diabetic patients should be monitored closely.
Sulindac: (Moderate) Nonsteroidal anti-inflammatory drugs (NSAIDs) may reduce the natriuretic effect of diuretics in some patients. NSAIDS have been associated with an inhibition of prostaglandin synthesis, which may result in reduced renal blood flow leading to renal insufficiency and increases in blood pressure that are often accompanied by peripheral edema and weight gain. Patients taking diuretics and NSAIDS concurrently are at higher risk of developing renal insufficiency. If an NSAID and a diuretic are used concurrently, carefully monitor the patient for signs and symptoms of decreased renal function and diuretic efficacy.
Sumatriptan; Naproxen: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant triamterene and naproxen use. Nonsteroidal antiinflammatory drugs (NSAIDs) may cause a dose-dependent reduction in renal blood flow, which may precipitate overt renal decompensation, and concomitant diuretic use increases the risk of this reaction. NSAIDs are associated with fluid retention which may blunt the cardiovascular effects of diuretics.
Tacrolimus: (Major) Avoid concomitant use of tacrolimus and potassium-sparing diuretics, such as triamterene, due to the risk of hyperkalemia. If concomitant use is necessary, closely monitor serum potassium concentrations.
Tapentadol: (Moderate) Monitor for decreased diuretic efficacy and additive orthostatic hypotension when potassium-sparing diuretics are administered with tapentadol. Adjustments to diuretic therapy may be needed in some patients. The efficacy of diuretics may be reduced due to opioid-induced release of antidiuretic hormone.
Telmisartan: (Moderate) Monitor serum potassium concentrations in patients receiving angiotensin II receptor antagonists concomitantly with triamterene. Concomitant use may result in hyperkalemia.
Telmisartan; Amlodipine: (Moderate) Monitor serum potassium concentrations in patients receiving angiotensin II receptor antagonists concomitantly with triamterene. Concomitant use may result in hyperkalemia.
Telmisartan; Hydrochlorothiazide, HCTZ: (Moderate) Monitor serum potassium concentrations in patients receiving angiotensin II receptor antagonists concomitantly with triamterene. Concomitant use may result in hyperkalemia.
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.
Thiazolidinediones: (Minor) Triamterene can interfere with the hypoglycemic effects of antidiabetic agents. This can lead to a loss of diabetic control, so diabetic patients should be monitored closely.
Thiothixene: (Moderate) Thiothixene should be used cautiously in patients receiving antihypertensive agents. Additive hypotensive effects are possible.
Tirzepatide: (Minor) Triamterene can decrease the hypoglycemic effects of antidiabetic agents, such as incretin mimetics, by producing an increase in blood glucose levels. Patients on antidiabetics should be monitored for changes in blood glucose control if triamterene is added or deleted. Dosage adjustments may be necessary.
Tizanidine: (Moderate) Monitor blood pressure during concomitant potassium-sparing diuretic and tizanidine use due to risk for additive hypotension.
Tolmetin: (Moderate) Nonsteroidal anti-inflammatory drugs (NSAIDs) may reduce the natriuretic effect of diuretics in some patients. NSAIDS have been associated with an inhibition of prostaglandin synthesis, which may result in reduced renal blood flow leading to renal insufficiency and increases in blood pressure that are often accompanied by peripheral edema and weight gain. Patients taking diuretics and NSAIDS concurrently are at higher risk of developing renal insufficiency. If an NSAID and a diuretic are used concurrently, carefully monitor the patient for signs and symptoms of decreased renal function and diuretic efficacy.
Tolterodine: (Minor) Diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Tolvaptan: (Moderate) Monitor serum potassium concentrations closely if tolvaptan and potassium-sparing diuretics are used together. In clinical studies, hyperkalemia was reported at a rate 1% to 2% higher when tolvaptan was administered with potassium-sparing diuretics compared to administration of these medications with placebo.
Tramadol: (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of triamterene and tramadol; increase the dosage of triamterene as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone.
Tramadol; Acetaminophen: (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of triamterene and tramadol; increase the dosage of triamterene as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone.
Trandolapril: (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.
Trandolapril; Verapamil: (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.
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.
Triamcinolone: (Minor) The manufacturer of spironolactone lists corticosteroids as a potential drug that interacts with spironolactone. Intensified electrolyte depletion, particularly hypokalemia, may occur. However, potassium-sparing diuretics such as spironolactone do not induce hypokalemia. In fact, hypokalemia is one of the indications for potassium-sparing diuretic therapy. Therefore, drugs that induce potassium loss, such as corticosteroids, could counter the hyperkalemic effects of potassium-sparing diuretics.
Trimethoprim: (Moderate) Monitor serum potassium concentrations if trimethoprim and a potassium-sparing diuretic are used together. Concomitant use may increase the risk of hyperkalemia. The risk for trimethoprim-associated hyperkalemia is greatest in patients with additional risk factors for hyperkalemia such as age greater than 65 years, those with underlying disorders of potassium metabolism, renal insufficiency, or those requiring high doses of trimethoprim.
Trospium: (Minor) In theory, coadministration of trospium with drugs which are eliminated by renal cationic secretion, such as triamterene, may increase the serum concentrations of trospium or triamterene due to competition for the drug elimination pathway.
Valsartan: (Moderate) Monitor serum potassium concentrations in patients receiving angiotensin II receptor antagonists concomitantly with triamterene. Concomitant use may result in hyperkalemia.
Valsartan; Hydrochlorothiazide, HCTZ: (Moderate) Monitor serum potassium concentrations in patients receiving angiotensin II receptor antagonists concomitantly with triamterene. Concomitant use may result in hyperkalemia.
Vemurafenib: (Minor) Concomitant use of vemurafenib and triamterene may result in increased triamterene concentrations. Vemurafenib is a CYP1A2 inhibitor and triamterene is a CYP1A2 substrate. Monitor patients for increased toxicity and hypotension.
Venlafaxine: (Moderate) Monitor for signs and symptoms of hyponatremia during concomitant diuretic and serotonin norepinephrine reuptake inhibitor (SNRI) use; consider discontinuing the SNRI if symptomatic hyponatremia occurs and institute appropriate medical intervention. Concomitant use increases the risk for developing hyponatremia.
Vilazodone: (Moderate) Patients receiving vilazodone with medications known to cause hyponatremia, such as diuretics, may be at increased risk of developing hyponatremia. Hyponatremia has occurred in association with the use of antidepressants such as selective serotonin reuptake inhibitors (SSRIs), serotonin norepinephrine reuptake inhibitors (SNRIs), and mirtazapine. Hyponatremia may manifest as headache, difficulty concentrating, memory impairment, confusion, weakness, and unsteadiness which may result in falls. Severe manifestations include hallucinations, syncope, seizure, coma, respiratory arrest, and death. Symptomatic hyponatremia may require discontinuation of vilazodone, as well as implementation of the appropriate medical interventions.
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.
Vortioxetine: (Moderate) Patients receiving a diuretic during treatment with vortioxetine may be at greater risk of developing syndrome of inappropriate antidiuretic hormone secretion (SIADH). Clinically significant hyponatremia has been reported during therapy with vortioxetine. One case involving serum sodium levels lower than 110 mmol/l has occurred. Hyponatremia may be potentiated by agents which can cause sodium depletion such as diuretics. Discontinuation of vortioxetine should be considered in patients who develop symptomatic hyponatremia.
Ziconotide: (Moderate) Patients taking diuretics with ziconotide may be at higher risk of depressed levels of consciousness. If altered consciousness occurs, consideration of diuretic cessation is warranted in addition to ziconotide discontinuation.
Ziprasidone: (Moderate) Additive hypotensive effects are possible if ziprasidone is used concurrently with antihypertensive agents. Ziprasidone is a moderate antagonist of alpha-1 receptors and may cause orthostatic hypotension with or without tachycardia, dizziness, or syncope.
Triamterene, like amiloride, inhibits the sodium-potassium ion exchange mechanism in the distal renal tubule independently of aldosterone. Triamterene appears to interfere with sodium reabsorption in the distal tubule by inhibiting sodium transport mechanisms directly, thereby setting up an electrical-potential difference across the membrane that blocks the passive distal tubular secretion of potassium. In conditions in which potassium loss is minimal, triamterene modifies distal tubule handling of potassium only slightly. If potassium renal clearance is increased by loop diuretics or mineralocorticoids, however, triamterene causes a significant drop in potassium excretion. Increased urinary excretion of sodium, bicarbonate, calcium, magnesium, chloride, and water lead to a slight diuresis. In addition, triamterene does not inhibit carbonic anhydrase activity. In general, diuretics worsen glucose tolerance and exert detrimental effects on the lipid profile.
Triamterene is administered orally.
Triamterene is approximately 67% bound to plasma proteins. Triamterene crosses the placenta, but it is not known whether it distributes into breast milk. However, animal studies have demonstrated small amounts in breast milk. Triamterene is a substrate for CYP1A2 and is metabolized to at least one active metabolite (p-hydroxytriamterene ester). Slightly less than 50% of triamterene and its metabolite are excreted in the urine. Roughly 21% of triamterene is eliminated unchanged. The remainder of the drug is eliminated via biliary/fecal routes. The half-life of triamterene is 1-2 hours in patients with normal renal function. The active metabolite has a half-life of approximately 3 hours in patients with normal renal function.
Affected cytochrome P450 (CYP450) enzymes and drug transporters: None known.
-Route-Specific Pharmacokinetics
Oral Route
Triamterene is rapidly but incompletely absorbed from the GI tract following oral administration; bioavailability is roughly 30-70%. The onset of action is 2-4 hours, with peak effects at 6-8 hours and a 12-16 hour duration of action.
-Special Populations
Hepatic Impairment
Cirrhosis is associated with a prolonged half-life of triamterene, by approximately four-fold.
Renal Impairment
In patients with chronic renal disease, the half-life of triamterene (10 hours) and the active metabolite is significantly increased, along with the risk of drug-induced hyperkalemia.
Geriatric
Drug accumulation of triamterene and its active metabolite has been reported in older patients; however, one report showed no change in drug disposition or pharmacodynamics of triamterene in the elderly.