Drug interactions
Dutasteride-tamsulosin + Phenobarbital
Severity: Moderate
Dutasteride-tamsulosin and Phenobarbital: moderate 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 induces CYP3A4 and may lower tamsulosin and dutasteride exposure. This may reduce effectiveness for BPH symptoms.
What this interaction means in plain words
Dutasteride-tamsulosin and Phenobarbital can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken.
Why it happens
Enzyme induction by phenobarbital increases metabolism of tamsulosin and dutasteride.
What to do
Monitor for diminished symptom control and consider alternative therapy if response is inadequate.
What to ask your pharmacist
- Should I take them at different times of day?
- Does the dose of either medicine need to change?
- Is there anything I should avoid, such as alcohol or certain foods, while on both?
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Other interactions of Dutasteride-tamsulosin
Frequently asked questions
Can I take Dutasteride-tamsulosin with Phenobarbital?
MediHelp rates the interaction as moderate. Dutasteride-tamsulosin and Phenobarbital can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken. Phenobarbital induces CYP3A4 and may lower tamsulosin and dutasteride exposure. This may reduce effectiveness for BPH symptoms.
How serious is the interaction between Dutasteride-tamsulosin and Phenobarbital?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor for diminished symptom control and consider alternative therapy if response is inadequate.
What other medicines interact with Dutasteride-tamsulosin?
MediHelp also lists interactions of Dutasteride-tamsulosin with, for example, Alfuzosin, Amifostine, Atazanavir. The full list is on the Dutasteride-tamsulosin page.
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