Drug interactions
Chlorthalidone + Losartan
Severity: Minor
Chlorthalidone and Losartan: minor 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
Losartan reduces aldosterone-mediated potassium loss and so tends to offset chlorthalidone-induced hypokalemia, while blood pressure lowering is additive. The combination is common and generally well tolerated, though potassium and renal function can change, and first-dose hypotension may occur in volume-depleted patients.
What this interaction means in plain words
Chlorthalidone and Losartan have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised.
Chlorthalidone belongs to Cardiovascular; Losartan belongs to Cardiovascular.
Why it happens
Thiazide-type kaliuresis is partly offset by angiotensin II receptor blockade, and both agents lower blood pressure by complementary mechanisms.
What to do
Check potassium and creatinine after initiation or dose changes and periodically afterwards. Watch for hypotension in volume-depleted patients.
What to ask your pharmacist
- Is there anything I should notice while taking both?
- Do I need to tell my doctor at the next visit?
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Other interactions of Chlorthalidone
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 Chlorthalidone with Losartan?
MediHelp rates the interaction as minor. Chlorthalidone and Losartan have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised. Losartan reduces aldosterone-mediated potassium loss and so tends to offset chlorthalidone-induced hypokalemia, while blood pressure lowering is additive. The combination is common and generally well tolerated, though potassium and renal function can change, and first-dose hypotension may occur in volume-depleted patients.
How serious is the interaction between Chlorthalidone and Losartan?
MediHelp rates it minor, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Check potassium and creatinine after initiation or dose changes and periodically afterwards. Watch for hypotension in volume-depleted patients.
What other medicines interact with Chlorthalidone?
MediHelp also lists interactions of Chlorthalidone with, for example, Amifostine, Atenolol-chlorthalidone, Candesartan-hydrochlorothiazide. The full list is on the Chlorthalidone page.
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