Drug interactions
Losartan + Potassium chloride
Severity: Major
Losartan and Potassium chloride: major interaction.
Last updated Sources: UK SmPC
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
Potassium chloride with losartan can cause hyperkalemia with risk of life-threatening arrhythmias, particularly in renal impairment, diabetes or heart failure.
What this interaction means in plain words
Losartan and Potassium chloride 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.
Losartan belongs to Cardiovascular; Potassium chloride belongs to Gastrointestinal Tract.
Why it happens
Losartan reduces aldosterone-mediated renal potassium excretion while the supplement adds a potassium load.
What to do
Avoid unless hypokalemia is documented; if combined, monitor serum potassium and renal function soon after starting and regularly thereafter, and reduce or stop the supplement if potassium rises.
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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References
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
Other interactions of Potassium chloride
Frequently asked questions
Can I take Losartan with Potassium chloride?
MediHelp rates the interaction as major. Losartan and Potassium chloride 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. Potassium chloride with losartan can cause hyperkalemia with risk of life-threatening arrhythmias, particularly in renal impairment, diabetes or heart failure.
How serious is the interaction between Losartan and Potassium chloride?
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 unless hypokalemia is documented; if combined, monitor serum potassium and renal function soon after starting and regularly thereafter, and reduce or stop the supplement if potassium rises.
What other medicines interact with Losartan?
MediHelp also lists interactions of Losartan with, for example, Aliskiren, Sparsentan, Amifostine. The full list is on the Losartan page.
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