Drug interactions
Captopril-hydrochlorothiazide + Triamterene
Severity: Major
Captopril-hydrochlorothiazide 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
Triamterene is a potassium-sparing diuretic and, with an ACE inhibitor, can cause serious hyperkalemia, particularly in renal impairment, diabetes or older age. The thiazide partly counters potassium retention, but this does not remove the risk. Additive blood pressure lowering and renal impairment may also occur.
What this interaction means in plain words
Captopril-hydrochlorothiazide 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-hydrochlorothiazide belongs to Cardiovascular; Triamterene belongs to Cardiovascular.
Why it happens
ACE inhibition reduces aldosterone-mediated potassium excretion while triamterene blocks distal sodium channels, both causing potassium retention.
What to do
Avoid unless hypokalemia is documented; if combined, check potassium and creatinine within the first week and periodically thereafter. Stop potassium supplements and salt substitutes.
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 Captopril-hydrochlorothiazide
- Aliskiren + Captopril-hydrochlorothiazide Contraindicated
- Captopril-hydrochlorothiazide + Dofetilide Contraindicated
- Captopril-hydrochlorothiazide + Sacubitril / valsartan Contraindicated
- Aceclofenac + Captopril-hydrochlorothiazide Major
- Aldesleukin + Captopril-hydrochlorothiazide Major
- Amifostine + Captopril-hydrochlorothiazide Major
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
Frequently asked questions
Can I take Captopril-hydrochlorothiazide with Triamterene?
MediHelp rates the interaction as major. Captopril-hydrochlorothiazide 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. Triamterene is a potassium-sparing diuretic and, with an ACE inhibitor, can cause serious hyperkalemia, particularly in renal impairment, diabetes or older age. The thiazide partly counters potassium retention, but this does not remove the risk. Additive blood pressure lowering and renal impairment may also occur.
How serious is the interaction between Captopril-hydrochlorothiazide 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 unless hypokalemia is documented; if combined, check potassium and creatinine within the first week and periodically thereafter. Stop potassium supplements and salt substitutes.
What other medicines interact with Captopril-hydrochlorothiazide?
MediHelp also lists interactions of Captopril-hydrochlorothiazide with, for example, Aliskiren, Dofetilide, Sacubitril / valsartan. The full list is on the Captopril-hydrochlorothiazide page.
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