Drug interactions
Captopril + Hydrochlorothiazide
Severity: Moderate
Captopril and Hydrochlorothiazide: moderate interaction.
Last updated
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
The combination lowers blood pressure more than either alone, and excessive hypotension can occur, especially at initiation in volume-depleted patients. Renal function may deteriorate in those with renal artery stenosis or dehydration.
What this interaction means in plain words
Captopril and Hydrochlorothiazide can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken.
Captopril belongs to Cardiovascular; Hydrochlorothiazide belongs to Cardiovascular.
Why it happens
Additive blood pressure lowering, with ACE inhibition reducing glomerular filtration pressure when volume is depleted.
What to do
Monitor blood pressure, creatinine and potassium after starting or adjusting therapy. Consider lowering or briefly holding the diuretic before starting captopril.
What to ask your pharmacist
- Should I take them at different times of day?
- Does the dose of either medicine need to change?
- Is there anything I should avoid, such as alcohol or certain foods, while on both?
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Other interactions of Hydrochlorothiazide
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 Hydrochlorothiazide?
MediHelp rates the interaction as moderate. Captopril and Hydrochlorothiazide can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken. The combination lowers blood pressure more than either alone, and excessive hypotension can occur, especially at initiation in volume-depleted patients. Renal function may deteriorate in those with renal artery stenosis or dehydration.
How serious is the interaction between Captopril and Hydrochlorothiazide?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor blood pressure, creatinine and potassium after starting or adjusting therapy. Consider lowering or briefly holding the diuretic before starting captopril.
What other medicines interact with Hydrochlorothiazide?
MediHelp also lists interactions of Hydrochlorothiazide with, for example, Dofetilide, Amifostine, Amiodarone. The full list is on the Hydrochlorothiazide page.
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