Drug interactions
Finasteride + Nelfinavir
Severity: Minor
Finasteride and Nelfinavir: 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
Nelfinavir inhibits CYP3A4 and may raise finasteride concentrations. Clinically important toxicity is unlikely given finasteride's tolerability.
What this interaction means in plain words
Finasteride and Nelfinavir have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised.
Finasteride belongs to Genitourinary; Nelfinavir belongs to Anti Virals.
Why it happens
Inhibition of CYP3A4-mediated finasteride metabolism.
What to do
No dose adjustment is required; monitor for finasteride adverse effects.
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?
Pro+ members
Unlock the full page
Create an account and start a Pro+ trial to unlock the full management advice for Finasteride and Nelfinavir, the additional notes, the evidence detail and the whole-prescription interaction checker.
- Full clinical management advice
- Additional notes
- Evidence detail
- Interaction checker for a whole prescription
Try Pro+ free for 7 days on the web. No card needed.
Other interactions of Finasteride
- Finasteride + Levoketoconazole Moderate
- Finasteride + Nefazodone Moderate
- Finasteride + Rifampin Moderate
- Finasteride + St john's wort Moderate
- Amobarbital + Finasteride Minor
- Aprepitant + Finasteride Minor
Other interactions of Nelfinavir
- Alfuzosin + Nelfinavir Contraindicated
- Avanafil + Nelfinavir Contraindicated
- Dronedarone + Nelfinavir Contraindicated
- Eletriptan + Nelfinavir Contraindicated
- Ergotamine + Nelfinavir Contraindicated
- Flibanserin + Nelfinavir Contraindicated
Frequently asked questions
Can I take Finasteride with Nelfinavir?
MediHelp rates the interaction as minor. Finasteride and Nelfinavir have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised. Nelfinavir inhibits CYP3A4 and may raise finasteride concentrations. Clinically important toxicity is unlikely given finasteride's tolerability.
How serious is the interaction between Finasteride and Nelfinavir?
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 dose adjustment is required; monitor for finasteride adverse effects.
What other medicines interact with Finasteride?
MediHelp also lists interactions of Finasteride with, for example, Levoketoconazole, Nefazodone, Rifampin. The full list is on the Finasteride page.
Full monographs, dosing and an interaction checker in the MediHelp app
Open the complete reference, check multi-drug interactions and use dosing tools in the MediHelp app.
