Drug interactions
Losartan + Metolazone
Severity: Moderate
Losartan 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 adds to the blood pressure lowering of losartan and can cause first-dose hypotension and volume depletion. Losartan tends to offset thiazide-induced potassium loss, while renal function may change.
What this interaction means in plain words
Losartan 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.
Losartan belongs to Cardiovascular; Metolazone belongs to Cardiovascular.
Why it happens
Additive antihypertensive effect from diuresis and angiotensin receptor blockade, with opposing effects on potassium handling.
What to do
Monitor blood pressure, serum potassium, sodium and creatinine after starting or changing doses. Reduce the diuretic dose if symptomatic hypotension occurs.
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?
Pro+ members
Unlock the full page
Create an account and start a Pro+ trial to unlock the full management advice for Losartan and Metolazone, the additional notes, the evidence detail and the whole-prescription interaction checker.
- Full clinical management advice
- Additional notes
- Evidence detail
- Interaction checker for a whole prescription
Try Pro+ free for 7 days on the web. No card needed.
Other interactions of Metolazone
Other interactions of Losartan
- Aliskiren + Losartan Contraindicated
- Losartan + Sparsentan Contraindicated
- Amifostine + Losartan Major
- Amiloride + Losartan Major
- Amlodipine-benazepril + Losartan Major
- Amlodipine-hydrochlorothiazide-valsartan + Losartan Major
Frequently asked questions
Can I take Losartan with Metolazone?
MediHelp rates the interaction as moderate. Losartan 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 adds to the blood pressure lowering of losartan and can cause first-dose hypotension and volume depletion. Losartan tends to offset thiazide-induced potassium loss, while renal function may change.
How serious is the interaction between Losartan 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 potassium, sodium and creatinine after starting or changing doses. Reduce the diuretic dose if symptomatic hypotension occurs.
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.
Full monographs, dosing and an interaction checker in the MediHelp app
Open the complete reference, check multi-drug interactions and use dosing tools in the MediHelp app.
