Drug interactions
Dutasteride + Phenobarbital
Severity: Minor
Dutasteride and Phenobarbital: 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
Phenobarbital is a well-known CYP3A4 inducer and may reduce dutasteride concentrations. This could lessen dutasteride's benefit during long-term use.
What this interaction means in plain words
Dutasteride and Phenobarbital have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised.
Why it happens
Induction of CYP3A4 by phenobarbital increases dutasteride metabolic clearance.
What to do
No routine dose change is needed. Reassess prostate symptoms or PSA response if clinical benefit appears reduced.
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 Dutasteride and Phenobarbital, 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 Dutasteride
- Dutasteride + Levoketoconazole Moderate
- Dutasteride + Nefazodone Moderate
- Dutasteride + Rifampin Moderate
- Dutasteride + St john's wort Moderate
- Amobarbital + Dutasteride Minor
- Aprepitant + Dutasteride Minor
Frequently asked questions
Can I take Dutasteride with Phenobarbital?
MediHelp rates the interaction as minor. Dutasteride and Phenobarbital have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised. Phenobarbital is a well-known CYP3A4 inducer and may reduce dutasteride concentrations. This could lessen dutasteride's benefit during long-term use.
How serious is the interaction between Dutasteride and Phenobarbital?
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. Reassess prostate symptoms or PSA response if clinical benefit appears reduced.
What other medicines interact with Dutasteride?
MediHelp also lists interactions of Dutasteride with, for example, Levoketoconazole, Nefazodone, Rifampin. The full list is on the Dutasteride 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.
