Drug interactions
Phenobarbital + Vardenafil
Severity: Moderate
Phenobarbital and Vardenafil: 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 can reduce vardenafil exposure, potentially causing treatment failure. The induction may persist for some weeks after phenobarbital is stopped.
What this interaction means in plain words
Phenobarbital and Vardenafil 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
Induction of CYP3A4 by phenobarbital increases vardenafil metabolism.
What to do
Monitor for loss of efficacy of vardenafil and consider an 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 Vardenafil
- Amyl nitrite + Vardenafil Contraindicated
- Glyceryl trinitrate pr + Vardenafil Contraindicated
- Isosorbide dinitrate + Vardenafil Contraindicated
- Isosorbide mononitrate + Vardenafil Contraindicated
- Nicorandil + Vardenafil Contraindicated
- Nitroglycerin po + Vardenafil Contraindicated
Frequently asked questions
Can I take Phenobarbital with Vardenafil?
MediHelp rates the interaction as moderate. Phenobarbital and Vardenafil 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 can reduce vardenafil exposure, potentially causing treatment failure. The induction may persist for some weeks after phenobarbital is stopped.
How serious is the interaction between Phenobarbital and Vardenafil?
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 loss of efficacy of vardenafil and consider an alternative therapy if response is inadequate.
What other medicines interact with Vardenafil?
MediHelp also lists interactions of Vardenafil with, for example, Amyl nitrite, Glyceryl trinitrate pr, Isosorbide dinitrate. The full list is on the Vardenafil page.
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