Abnormal elevation of serum potassium levels (at least 5.5 mEq/L) can occur with all potassium-sparing agents, including triamterene. Hyperkalemia is more likely to occur in patients with renal impairment and diabetes (even without evidence of renal impairment), and in elderly or severely ill patients. Because uncorrected hyperkalemia may be fatal, serum potassium levels must be monitored at frequent intervals especially in patients receiving triamterene, when dosages are changed, or with any illness that may influence renal function.
Edema:
Note: Although included as an FDA-approved use in the manufacturer's prescribing information for the management of edema, other diuretics are preferred in clinical practice (Ref).
Oral: Initial: 50 to 100 mg once daily; titrate as needed based on patient response. Maximum: 300 mg/day in divided doses (Ref).
Dosage adjustment for concomitant therapy: Significant drug interactions exist, requiring dose/frequency adjustment or avoidance. Consult drug interactions database for more information.
CrCl ≤50 mL/minute: Avoid use (Ref).
Manufacturer's labeling:
Mild to moderate impairment: There are no dosage adjustments provided in the manufacturer's labeling.
Severe impairment, progressive kidney disease, or anuria: Use is contraindicated.
Mild to moderate impairment: There are no dosage adjustments provided in the manufacturer's labeling (has not been studied).
Severe impairment: Use is contraindicated.
Refer to adult dosing. In the management of hypertension, consider lower initial doses and titrate to response (Ref).
(For additional information see "Triamterene: Pediatric drug information")
Edema: Children and Adolescents: Limited data available: Oral: 1 to 4 mg/kg/day divided into 1 to 2 doses; maximum daily dose: 6 mg/kg/day or 300 mg/day, whichever is lower (Ref)
Hypertension: Limited data available: Children and Adolescents: Oral: Initial: 0.5 to 1 mg/kg/dose twice daily; maximum daily dose: 3 to 4 mg/kg/day or 300 mg/day, whichever is lower (Ref)
Dosage adjustment for concomitant therapy: Significant drug interactions exist, requiring dose/frequency adjustment or avoidance. Consult drug interactions database for more information.
Mild to moderate impairment: There are no dosage adjustments provided in the manufacturer's labeling; use with caution, monitor serum potassium.
Severe impairment or progressive kidney disease: Use is contraindicated.
Mild to moderate impairment: There are no dosage adjustments provided in the manufacturer's labeling.
Severe hepatic disease: Use is contraindicated.
The following adverse drug reactions and incidences are derived from product labeling unless otherwise specified. Frequency not defined.
Central nervous system: Dizziness, fatigue, headache
Dermatologic: Skin photosensitivity, skin rash
Endocrine & metabolic: Hyperkalemia, hypokalemia, increased uric acid, metabolic acidosis
Gastrointestinal: Diarrhea, nausea, vomiting, xerostomia
Genitourinary: Azotemia
Hematologic & oncologic: Hematologic abnormality, megaloblastic anemia, thrombocytopenia
Hepatic: Jaundice, liver enzyme disorder
Hypersensitivity: Anaphylaxis
Neuromuscular & skeletal: Weakness
Renal: Acute interstitial nephritis (rare), acute renal failure (rare), increased blood urea nitrogen, increased serum creatinine, nephrolithiasis
Hypersensitivity to triamterene or any component of the formulation; anuria; severe or progressive kidney disease or dysfunction with the possible exception of nephrosis; severe hepatic disease; hyperkalemia; coadministration with other potassium-sparing agents or other formulations containing triamterene
Significant drug interactions exist, requiring dose/frequency adjustment or avoidance. Consult drug interactions database for more information.
Concerns related to adverse effects:
• Fluid/electrolyte loss: Triamterene can lead to profound diuresis with fluid and electrolyte loss; close medical supervision and dose evaluation are required. Patients with heart failure, renal disease, or cirrhosis may be particularly susceptible to fluid and electrolyte abnormalities. Watch for and correct electrolyte disturbances; adjust dose to avoid dehydration.
• Hyperkalemia: [US Boxed Warning]: Hyperkalemia can occur; patients at risk include those with renal impairment, diabetes, the elderly, and the severely ill. Serum potassium levels must be monitored at frequent intervals especially when dosages are changed or with any illness that may cause renal dysfunction. . In patients who develop hyperkalemia or if hyperkalemia is suspected, obtain an electrocardiogram to rule out hyperkalemia-induced QRS prolongation or other cardiac arrhythmias. Discontinue triamterene and any potassium supplementation in patients who develop hyperkalemia; treat cardiac arrhythmias as clinically indicated.
• Hypersensitivity reactions: Isolated occurrences have been reported. Observe for blood dyscrasias, liver damage or idiosyncratic reactions
• Photosensitivity: Can cause photosensitivity.
Disease-related concerns:
• Adrenal insufficiency: Avoid use of diuretics for treatment of elevated blood pressure in patients with primary adrenal insufficiency (Addison disease). Adjustment of glucocorticoid/mineralocorticoid therapy and/or use of other antihypertensive agents is preferred to treat hypertension (Bornstein 2016; Inder 2015).
• Diabetes: Use with caution in patients with prediabetes or diabetes mellitus; may increase blood glucose concentrations and necessitate dosage adjustment of hypoglycemic agents.
• Gout: May cause elevation in uric acid.
• Hepatic impairment: Use with caution in patients with severe hepatic dysfunction; in cirrhosis, avoid electrolyte and acid/base imbalances that might lead to hepatic encephalopathy.
• Kidney stones: Use with caution in patients with kidney stones.
Other warnings/precautions:
• Abrupt discontinuation: In patients who have received triamterene for prolonged periods of time, a hypothetical risk of rebound kaliuresis may occur when abruptly discontinued; withdraw triamterene gradually in these patients.
Excipient information presented when available (limited, particularly for generics); consult specific product labeling.
Capsule, Oral:
Dyrenium: 50 mg, 100 mg [contains fd&c yellow #6 (sunset yellow)]
Generic: 50 mg, 100 mg
Yes
Capsules (Dyrenium Oral)
50 mg (per each): $17.81
100 mg (per each): $17.81
Capsules (Triamterene Oral)
50 mg (per each): $11.93 - $11.94
100 mg (per each): $11.93 - $11.94
Disclaimer: A representative AWP (Average Wholesale Price) price or price range is provided as reference price only. A range is provided when more than one manufacturer's AWP price is available and uses the low and high price reported by the manufacturers to determine the range. The pricing data should be used for benchmarking purposes only, and as such should not be used alone to set or adjudicate any prices for reimbursement or purchasing functions or considered to be an exact price for a single product and/or manufacturer. Medi-Span expressly disclaims all warranties of any kind or nature, whether express or implied, and assumes no liability with respect to accuracy of price or price range data published in its solutions. In no event shall Medi-Span be liable for special, indirect, incidental, or consequential damages arising from use of price or price range data. Pricing data is updated monthly.
Oral: Administer after meals.
Oral: Administer with food to avoid GI upset
Edema: Although included as an FDA-approved use in the manufacturer's prescribing information for the management of edema, other diuretics are preferred in clinical practice (AHA/ACC/HFSA [Heidenreich 2022]; Brater 2022).
Triamterene may be confused with trimipramine
Dyrenium may be confused with Pyridium
Beers Criteria: Diuretics are identified in the Beers Criteria as potentially inappropriate medications to be used with caution in patients 65 years and older due to the potential to cause or exacerbate syndrome of inappropriate antidiuretic hormone secretion (SIADH) or hyponatremia; monitor sodium concentration closely when initiating or adjusting the dose in older adults (Beers Criteria [AGS 2023]).
Substrate of OCT2;
Note: Interacting drugs may not be individually listed below if they are part of a group interaction (eg, individual drugs within “CYP3A4 Inducers [Strong]” are NOT listed). For a complete list of drug interactions by individual drug name and detailed management recommendations, use the drug interactions program by clicking on the “Launch drug interactions program” link above.
Alfuzosin: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Aliskiren: Potassium-Sparing Diuretics may increase hyperkalemic effects of Aliskiren. Risk C: Monitor
Amifostine: Blood Pressure Lowering Agents may increase hypotensive effects of Amifostine. Management: When used at chemotherapy doses, hold blood pressure lowering medications for 24 hours before amifostine administration. If blood pressure lowering therapy cannot be held, do not administer amifostine. Use caution with radiotherapy doses of amifostine. Risk D: Consider Therapy Modification
Ammonium Chloride: Potassium-Sparing Diuretics may increase adverse/toxic effects of Ammonium Chloride. Specifically the risk of systemic acidosis. Risk C: Monitor
Amphetamines: May decrease antihypertensive effects of Antihypertensive Agents. Risk C: Monitor
Angiotensin II Receptor Blockers: Potassium-Sparing Diuretics may increase hyperkalemic effects of Angiotensin II Receptor Blockers. Risk C: Monitor
Angiotensin-Converting Enzyme Inhibitors: Potassium-Sparing Diuretics may increase hyperkalemic effects of Angiotensin-Converting Enzyme Inhibitors. Risk C: Monitor
Antipsychotic Agents (Second Generation [Atypical]): Blood Pressure Lowering Agents may increase hypotensive effects of Antipsychotic Agents (Second Generation [Atypical]). Risk C: Monitor
Arginine: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Arimoclomol: May increase serum concentration of OCT2 Substrates (Clinically Relevant with Inhibitors). Risk C: Monitor
Barbiturates: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Benperidol: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Brigatinib: May decrease antihypertensive effects of Antihypertensive Agents. Brigatinib may increase bradycardic effects of Antihypertensive Agents. Risk C: Monitor
Brimonidine (Topical): May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Bromperidol: May decrease hypotensive effects of Blood Pressure Lowering Agents. Blood Pressure Lowering Agents may increase hypotensive effects of Bromperidol. Risk X: Avoid
CycloSPORINE (Systemic): Potassium-Sparing Diuretics may increase hyperkalemic effects of CycloSPORINE (Systemic). Risk X: Avoid
Desmopressin: Hyponatremia-Associated Agents may increase hyponatremic effects of Desmopressin. Risk C: Monitor
Dexmethylphenidate: May decrease therapeutic effects of Antihypertensive Agents. Risk C: Monitor
Diacerein: May increase therapeutic effects of Diuretics. Specifically, the risk for dehydration or hypokalemia may be increased. Risk C: Monitor
Diazoxide: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Digitoxin: Potassium-Sparing Diuretics may increase adverse/toxic effects of Digitoxin. Potassium-Sparing Diuretics may decrease therapeutic effects of Digitoxin. Risk C: Monitor
Dofetilide: Triamterene may increase serum concentration of Dofetilide. Risk C: Monitor
Drospirenone-Containing Products: May increase hyperkalemic effects of Potassium-Sparing Diuretics. Risk C: Monitor
DULoxetine: Blood Pressure Lowering Agents may increase hypotensive effects of DULoxetine. Risk C: Monitor
Fedratinib: May increase serum concentration of OCT2 Substrates (Clinically Relevant with Inhibitors). Risk C: Monitor
Fexinidazole: May increase serum concentration of OCT2 Substrates (Clinically Relevant with Inhibitors). Management: Avoid use of fexinidazole with OCT2 substrates when possible. If combined, monitor for increased OCT2 substrate toxicities. Risk D: Consider Therapy Modification
Finerenone: Potassium-Sparing Diuretics may increase hyperkalemic effects of Finerenone. Risk C: Monitor
Flunarizine: May increase therapeutic effects of Antihypertensive Agents. Risk C: Monitor
Givinostat: May increase serum concentration of OCT2 Substrates (Clinically Relevant with Inhibitors). Risk C: Monitor
Heparin: May increase hyperkalemic effects of Potassium-Sparing Diuretics. Risk C: Monitor
Heparins (Low Molecular Weight): May increase hyperkalemic effects of Potassium-Sparing Diuretics. Risk C: Monitor
Herbal Products with Blood Pressure Increasing Effects: May decrease antihypertensive effects of Antihypertensive Agents. Risk C: Monitor
Herbal Products with Blood Pressure Lowering Effects: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Hypotension-Associated Agents: Blood Pressure Lowering Agents may increase hypotensive effects of Hypotension-Associated Agents. Risk C: Monitor
Iloperidone: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Indomethacin: Triamterene may increase adverse/toxic effects of Indomethacin. Specifically, the risk for renal failure and hyperkalemia may be increased. Management: Consider alternatives to concomitant treatment with triamterene and indomethacin. If the combination cannot be avoided, monitor for development of renal failure and hyperkalemia. Risk D: Consider Therapy Modification
Indoramin: May increase hypotensive effects of Antihypertensive Agents. Risk C: Monitor
Isocarboxazid: May increase hypotensive effects of Diuretics. Risk X: Avoid
Levodopa-Foslevodopa: Blood Pressure Lowering Agents may increase hypotensive effects of Levodopa-Foslevodopa. Risk C: Monitor
Lithium: Potassium-Sparing Diuretics may decrease serum concentration of Lithium. Potassium-Sparing Diuretics may increase serum concentration of Lithium. Risk C: Monitor
Loop Diuretics: May increase hypotensive effects of Antihypertensive Agents. Risk C: Monitor
Lormetazepam: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Metergoline: May decrease antihypertensive effects of Blood Pressure Lowering Agents. Blood Pressure Lowering Agents may increase orthostatic hypotensive effects of Metergoline. Risk C: Monitor
Methylphenidate: May decrease antihypertensive effects of Antihypertensive Agents. Risk C: Monitor
Molsidomine: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Naftopidil: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Nicergoline: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Nicorandil: May increase hyperkalemic effects of Potassium-Sparing Diuretics. Risk C: Monitor
Nicorandil: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Nitroprusside: Blood Pressure Lowering Agents may increase hypotensive effects of Nitroprusside. Risk C: Monitor
Nonsteroidal Anti-Inflammatory Agents: May increase hyperkalemic effects of Potassium-Sparing Diuretics. Nonsteroidal Anti-Inflammatory Agents may decrease antihypertensive effects of Potassium-Sparing Diuretics. Risk C: Monitor
Obinutuzumab: May increase hypotensive effects of Blood Pressure Lowering Agents. Management: Consider temporarily withholding blood pressure lowering medications beginning 12 hours prior to obinutuzumab infusion and continuing until 1 hour after the end of the infusion. Risk D: Consider Therapy Modification
Opioid Agonists: May increase adverse/toxic effects of Diuretics. Opioid Agonists may decrease therapeutic effects of Diuretics. Risk C: Monitor
Pentoxifylline: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Perazine: May increase hypotensive effects of Antihypertensive Agents. Risk C: Monitor
Pholcodine: Blood Pressure Lowering Agents may increase hypotensive effects of Pholcodine. Risk C: Monitor
Phosphodiesterase 5 Inhibitors: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Piperacillin: May increase hypokalemic effects of Diuretics. Risk C: Monitor
Polyethylene Glycol-Electrolyte Solution: Diuretics may increase nephrotoxic effects of Polyethylene Glycol-Electrolyte Solution. Risk C: Monitor
Potassium Salts: May increase hyperkalemic effects of Triamterene. Risk X: Avoid
Potassium-Sparing Diuretics: May increase hyperkalemic effects of Potassium-Sparing Diuretics. Risk X: Avoid
Pramipexole: Triamterene may increase hypotensive effects of Pramipexole. Triamterene may increase serum concentration of Pramipexole. Risk C: Monitor
Prazosin: Antihypertensive Agents may increase hypotensive effects of Prazosin. Risk C: Monitor
Prostacyclin Analogues: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Quinagolide: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Silodosin: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Sodium Phosphates: Diuretics may increase nephrotoxic effects of Sodium Phosphates. Specifically, the risk of acute phosphate nephropathy may be enhanced. Risk C: Monitor
Tacrolimus (Systemic): Potassium-Sparing Diuretics may increase hyperkalemic effects of Tacrolimus (Systemic). Risk C: Monitor
Tafenoquine: May increase serum concentration of OCT2 Substrates (Clinically Relevant with Inhibitors). Management: Avoid use of OCT2 substrates with tafenoquine, and if the combination cannot be avoided, monitor closely for evidence of toxicity of the OCT2 substrate and consider a reduced dose of the OCT2 substrate according to that substrate's labeling. Risk D: Consider Therapy Modification
Terazosin: Antihypertensive Agents may increase hypotensive effects of Terazosin. Risk C: Monitor
Tolvaptan: May increase hyperkalemic effects of Potassium-Sparing Diuretics. Risk C: Monitor
Trimethoprim: May increase hyperkalemic effects of Potassium-Sparing Diuretics. Risk C: Monitor
Urapidil: Antihypertensive Agents may increase hypotensive effects of Urapidil. Risk C: Monitor
Vimseltinib: May increase serum concentration of OCT2 Substrates (Clinically Relevant with Inhibitors). Management: Avoid concomitant use of vimseltinib and OCT2 substrates when possible. If combined, monitor for increased effects and toxicities of the OCT2 substrate and consider dose adjustments. Risk D: Consider Therapy Modification
Triamterene crosses the placenta and is found in cord blood. Use of triamterene to treat edema during normal pregnancies is not appropriate; use may be considered when edema is due to pathologic causes (as in the nonpregnant patient); monitor.
It is not known if triamterene is present in breast milk. Breastfeeding is not recommended by the manufacturer.
Blood pressure; serum electrolytes (especially potassium); kidney function; fluid intake and output.
Blocks epithelial sodium channels in the late distal convoluted tubule (DCT) and collecting duct which inhibits sodium reabsorption from the lumen. This effectively reduces intracellular sodium, decreasing the function of Na+/K+ ATPase, leading to potassium retention and decreased calcium, magnesium, and hydrogen excretion. As sodium uptake capacity in the DCT/collecting duct is limited, the natriuretic, diuretic, and antihypertensive effects are generally considered weak.
Onset of action: Diuresis: 2 to 4 hours; Note: Maximum therapeutic effect may not occur until after several days of therapy
Duration: Diuresis: 7 to 9 hours
Absorption: Rapid
Metabolism: Primarily metabolized to the sulfate conjugate of hydroxytriamterene
Time to peak, plasma: ~3 hours
Excretion: Urine (21% to <50%; primarily as metabolites)