Drug interactions
Fluoxetine + Hydrochlorothiazide-losartan
Severity: Minor
Fluoxetine and Hydrochlorothiazide-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
Fluoxetine inhibits CYP2C9 and CYP2C19 to some extent, which could reduce conversion of losartan to its active metabolite. The clinical importance is uncertain and usually small. Fluoxetine may also contribute to hyponatremia alongside the thiazide.
What this interaction means in plain words
Fluoxetine and Hydrochlorothiazide-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.
Fluoxetine belongs to Central Nervous System; Hydrochlorothiazide-losartan belongs to Cardiovascular.
Why it happens
Possible CYP2C9 inhibition by fluoxetine reducing formation of the active metabolite E-3174.
What to do
Monitor blood pressure after starting or changing fluoxetine. Check sodium in older patients since both drugs can cause hyponatremia.
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 Fluoxetine
- Fluoxetine + Isocarboxazid Contraindicated
- Fluoxetine + Mavacamten Contraindicated
- Fluoxetine + Methylene blue Contraindicated
- Fluoxetine + Phenelzine Contraindicated
- Fluoxetine + Pimozide Contraindicated
- Fluoxetine + Rasagiline Contraindicated
Frequently asked questions
Can I take Fluoxetine with Hydrochlorothiazide-losartan?
MediHelp rates the interaction as minor. Fluoxetine and Hydrochlorothiazide-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. Fluoxetine inhibits CYP2C9 and CYP2C19 to some extent, which could reduce conversion of losartan to its active metabolite. The clinical importance is uncertain and usually small. Fluoxetine may also contribute to hyponatremia alongside the thiazide.
How serious is the interaction between Fluoxetine and Hydrochlorothiazide-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: Monitor blood pressure after starting or changing fluoxetine. Check sodium in older patients since both drugs can cause hyponatremia.
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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