Drug interactions
Hydrochlorothiazide-losartan + Mefenamic acid
Severity: Moderate
Hydrochlorothiazide-losartan and Mefenamic acid: 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
Mefenamic acid can blunt the antihypertensive action of losartan and hydrochlorothiazide. With an ARB and diuretic it raises the risk of acute kidney injury and hyperkalemia, particularly with dehydration.
What this interaction means in plain words
Hydrochlorothiazide-losartan and Mefenamic acid 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.
Hydrochlorothiazide-losartan belongs to Cardiovascular; Mefenamic acid belongs to Musculoskeletal.
Why it happens
NSAID inhibition of renal prostaglandin synthesis reduces renal blood flow and sodium excretion, opposing ARB and diuretic effects.
What to do
Use the shortest course at the lowest dose and maintain hydration. Monitor blood pressure, creatinine and potassium.
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?
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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
Other interactions of Mefenamic acid
- Ketorolac intranasal + Mefenamic acid Contraindicated
- Ketorolac + Mefenamic acid Contraindicated
- Aceclofenac + Mefenamic acid Major
- Acemetacin + Mefenamic acid Major
- Acetylsalicylic acid + Mefenamic acid Major
- Alteplase + Mefenamic acid Major
Frequently asked questions
Can I take Hydrochlorothiazide-losartan with Mefenamic acid?
MediHelp rates the interaction as moderate. Hydrochlorothiazide-losartan and Mefenamic acid 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. Mefenamic acid can blunt the antihypertensive action of losartan and hydrochlorothiazide. With an ARB and diuretic it raises the risk of acute kidney injury and hyperkalemia, particularly with dehydration.
How serious is the interaction between Hydrochlorothiazide-losartan and Mefenamic acid?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Use the shortest course at the lowest dose and maintain hydration. Monitor blood pressure, creatinine and potassium.
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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