Drug interactions
Hydrochlorothiazide-losartan + Potassium phosphates
Severity: Major
Hydrochlorothiazide-losartan and Potassium phosphates: 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
Losartan reduces aldosterone-mediated potassium excretion, and intravenous potassium phosphates deliver a potassium load. The combination can cause hyperkalemia, especially in renal impairment, and may cause arrhythmias. The thiazide partly offsets this by increasing potassium loss.
What this interaction means in plain words
Hydrochlorothiazide-losartan and Potassium phosphates 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.
Why it happens
Additive potassium elevation from ARB-mediated reduced renal potassium excretion and exogenous potassium administration.
What to do
Check serum potassium, phosphate, and renal function before and frequently during infusion, and use the lowest effective dose and slow rate. Consider holding losartan 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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Other interactions of Hydrochlorothiazide-losartan
- Aliskiren + Hydrochlorothiazide-losartan Contraindicated
- Dofetilide + Hydrochlorothiazide-losartan Contraindicated
- Hydrochlorothiazide-losartan + Sparsentan Contraindicated
- Aceclofenac + Hydrochlorothiazide-losartan Major
- Aldesleukin + Hydrochlorothiazide-losartan Major
- Amifostine + Hydrochlorothiazide-losartan Major
Frequently asked questions
Can I take Hydrochlorothiazide-losartan with Potassium phosphates?
MediHelp rates the interaction as major. Hydrochlorothiazide-losartan and Potassium phosphates 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 reduces aldosterone-mediated potassium excretion, and intravenous potassium phosphates deliver a potassium load. The combination can cause hyperkalemia, especially in renal impairment, and may cause arrhythmias. The thiazide partly offsets this by increasing potassium loss.
How serious is the interaction between Hydrochlorothiazide-losartan and Potassium phosphates?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Check serum potassium, phosphate, and renal function before and frequently during infusion, and use the lowest effective dose and slow rate. Consider holding losartan if potassium rises.
What other medicines interact with Hydrochlorothiazide-losartan?
MediHelp also lists interactions of Hydrochlorothiazide-losartan with, for example, Aliskiren, Dofetilide, Sparsentan. The full list is on the Hydrochlorothiazide-losartan page.
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