Drug interactions
Captopril + Metolazone
Severity: Moderate
Captopril and Metolazone: 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
Metolazone with captopril produces additive blood pressure lowering, with a risk of marked hypotension particularly after the first dose or in volume-depleted patients. Renal function may also deteriorate.
What this interaction means in plain words
Captopril and Metolazone 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; Metolazone belongs to Cardiovascular.
Why it happens
Diuretic-induced volume depletion activates the renin-angiotensin system, so ACE inhibition causes exaggerated hypotension and reduced glomerular filtration.
What to do
Monitor blood pressure, serum creatinine and electrolytes when starting or adjusting therapy. Consider reducing or temporarily holding the diuretic before starting captopril in volume-depleted patients.
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 Metolazone
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 Metolazone?
MediHelp rates the interaction as moderate. Captopril and Metolazone 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. Metolazone with captopril produces additive blood pressure lowering, with a risk of marked hypotension particularly after the first dose or in volume-depleted patients. Renal function may also deteriorate.
How serious is the interaction between Captopril and Metolazone?
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, serum creatinine and electrolytes when starting or adjusting therapy. Consider reducing or temporarily holding the diuretic before starting captopril in volume-depleted patients.
What other medicines interact with Metolazone?
MediHelp also lists interactions of Metolazone with, for example, Amifostine, Amlodipine-hydrochlorothiazide-valsartan, Amlodipine-olmesartan-hydrochlorothiazide. The full list is on the Metolazone page.
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