Drug interactions
Finasteride + Ritonavir
Severity: Minor
Finasteride and Ritonavir: 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
Ritonavir is a strong CYP3A4 inhibitor and may raise finasteride levels. Because finasteride is well tolerated across a wide exposure range, the clinical impact is expected to be limited.
What this interaction means in plain words
Finasteride and Ritonavir 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; Ritonavir belongs to Anti Virals.
Why it happens
Inhibition of CYP3A4-mediated finasteride metabolism by ritonavir.
What to do
No dose adjustment is generally required. Monitor for increased finasteride adverse effects such as sexual dysfunction.
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 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 Ritonavir
- Alfuzosin + Ritonavir Contraindicated
- Amiodarone + Ritonavir Contraindicated
- Avanafil + Ritonavir Contraindicated
- Colchicine + Ritonavir Contraindicated
- Dronedarone + Ritonavir Contraindicated
- Eletriptan + Ritonavir Contraindicated
Frequently asked questions
Can I take Finasteride with Ritonavir?
MediHelp rates the interaction as minor. Finasteride and Ritonavir have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised. Ritonavir is a strong CYP3A4 inhibitor and may raise finasteride levels. Because finasteride is well tolerated across a wide exposure range, the clinical impact is expected to be limited.
How serious is the interaction between Finasteride and Ritonavir?
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 generally required. Monitor for increased finasteride adverse effects such as sexual dysfunction.
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.
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