Drug interactions
Hydrochlorothiazide-olmesartan + Metolazone
Severity: Major
Hydrochlorothiazide-olmesartan and Metolazone: major 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 added to a thiazide produces sequential nephron blockade with a strong diuretic effect. This can cause marked hypokalemia, hyponatremia, volume depletion, hypotension and renal impairment, and olmesartan adds to the hypotension and renal risk.
What this interaction means in plain words
Hydrochlorothiazide-olmesartan and Metolazone 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.
Hydrochlorothiazide-olmesartan belongs to Cardiovascular; Metolazone belongs to Cardiovascular.
Why it happens
Additive inhibition of the sodium-chloride cotransporter causes excessive natriuresis and potassium loss, with ARB reducing glomerular perfusion pressure.
What to do
Avoid duplicate thiazide-type therapy unless intentionally used for resistant edema under supervision. Monitor electrolytes, creatinine, weight and blood pressure closely.
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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Other interactions of Hydrochlorothiazide-olmesartan
- Aliskiren + Hydrochlorothiazide-olmesartan Contraindicated
- Dofetilide + Hydrochlorothiazide-olmesartan Contraindicated
- Hydrochlorothiazide-olmesartan + Sparsentan Contraindicated
- Acemetacin + Hydrochlorothiazide-olmesartan Major
- Amifostine + Hydrochlorothiazide-olmesartan Major
- Amiloride + Hydrochlorothiazide-olmesartan Major
Other interactions of Metolazone
Frequently asked questions
Can I take Hydrochlorothiazide-olmesartan with Metolazone?
MediHelp rates the interaction as major. Hydrochlorothiazide-olmesartan and Metolazone 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. Metolazone added to a thiazide produces sequential nephron blockade with a strong diuretic effect. This can cause marked hypokalemia, hyponatremia, volume depletion, hypotension and renal impairment, and olmesartan adds to the hypotension and renal risk.
How serious is the interaction between Hydrochlorothiazide-olmesartan and Metolazone?
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 duplicate thiazide-type therapy unless intentionally used for resistant edema under supervision. Monitor electrolytes, creatinine, weight and blood pressure closely.
What other medicines interact with Hydrochlorothiazide-olmesartan?
MediHelp also lists interactions of Hydrochlorothiazide-olmesartan with, for example, Aliskiren, Dofetilide, Sparsentan. The full list is on the Hydrochlorothiazide-olmesartan page.
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