Drug interactions
Hydrochlorothiazide-losartan + Metronidazole
Severity: Minor
Hydrochlorothiazide-losartan and Metronidazole: 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
Metronidazole may inhibit CYP2C9 and could reduce conversion of losartan to its active metabolite. The clinical effect is not established and any change in blood pressure control is likely small.
What this interaction means in plain words
Hydrochlorothiazide-losartan and Metronidazole have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised.
Hydrochlorothiazide-losartan belongs to Cardiovascular; Metronidazole belongs to Anti Parasitic.
Why it happens
Possible CYP2C9 inhibition reduces formation of losartan's active metabolite E-3174.
What to do
No routine dose change is needed. Monitor blood pressure if metronidazole is given for a prolonged course.
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 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 Metronidazole
- Ethanol + Metronidazole Contraindicated
- Metronidazole + Pimozide Contraindicated
- Amiodarone + Metronidazole Major
- Disulfiram + Metronidazole Major
- Ergotamine + Metronidazole Major
- Lomitapide + Metronidazole Major
Frequently asked questions
Can I take Hydrochlorothiazide-losartan with Metronidazole?
MediHelp rates the interaction as minor. Hydrochlorothiazide-losartan and Metronidazole have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised. Metronidazole may inhibit CYP2C9 and could reduce conversion of losartan to its active metabolite. The clinical effect is not established and any change in blood pressure control is likely small.
How serious is the interaction between Hydrochlorothiazide-losartan and Metronidazole?
MediHelp rates it minor, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: No routine dose change is needed. Monitor blood pressure if metronidazole is given for a prolonged course.
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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