Drug interactions
Captopril + Triamterene
Severity: Major
Captopril and Triamterene: major interaction.
Last updated Sources: US FDA label
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
ACE inhibitors reduce aldosterone and, together with triamterene, can cause clinically significant hyperkalemia, especially in renal impairment, diabetes or older age. Additive blood pressure lowering may also occur.
What this interaction means in plain words
Captopril and Triamterene can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for.
Captopril belongs to Cardiovascular; Triamterene belongs to Cardiovascular.
Why it happens
ACE inhibition lowers aldosterone-mediated potassium excretion while triamterene blocks distal sodium channels, giving additive potassium retention.
What to do
Avoid the combination where possible; if used, check potassium and creatinine within the first week and periodically thereafter. Avoid potassium supplements and salt substitutes and stop triamterene if hyperkalemia develops.
What to ask your pharmacist
- Does the benefit of taking both outweigh the risk in my case?
- Do I need any blood test, ECG or other check while on both?
- What early warning signs should I watch for, and what should I do if they appear?
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References
Other interactions of Triamterene
- Amiloride + Triamterene Contraindicated
- Eplerenone + Triamterene Contraindicated
- Potassium citrate / citric acid + Triamterene Contraindicated
- Potassium citrate + Triamterene Contraindicated
- Spironolactone + Triamterene Contraindicated
- Aceclofenac + Triamterene Major
Other interactions of Captopril
- Aliskiren + Captopril Contraindicated
- Captopril + Sacubitril / valsartan Contraindicated
- Captopril + Sacubitril-valsartan Contraindicated
- Amifostine + Captopril Major
- Amiloride + Captopril Major
- Amlodipine-hydrochlorothiazide-valsartan + Captopril Major
Frequently asked questions
Can I take Captopril with Triamterene?
MediHelp rates the interaction as major. Captopril and Triamterene can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for. ACE inhibitors reduce aldosterone and, together with triamterene, can cause clinically significant hyperkalemia, especially in renal impairment, diabetes or older age. Additive blood pressure lowering may also occur.
How serious is the interaction between Captopril and Triamterene?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Avoid the combination where possible; if used, check potassium and creatinine within the first week and periodically thereafter. Avoid potassium supplements and salt substitutes and stop triamterene if hyperkalemia develops.
What other medicines interact with Triamterene?
MediHelp also lists interactions of Triamterene with, for example, Amiloride, Eplerenone, Potassium citrate / citric acid. The full list is on the Triamterene page.
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