Drug interactions
Phenobarbital + Vinblastine
Severity: Moderate
Phenobarbital and Vinblastine: 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 P-glycoprotein and may lower vinblastine exposure. This could reduce anticancer efficacy.
What this interaction means in plain words
Phenobarbital and Vinblastine 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
Phenobarbital induces CYP3A4 and P-glycoprotein, increasing vinblastine metabolism and efflux.
What to do
Where possible, use a non-inducing anticonvulsant such as levetiracetam. If phenobarbital is required, monitor for reduced response to vinblastine.
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 Vinblastine
Frequently asked questions
Can I take Phenobarbital with Vinblastine?
MediHelp rates the interaction as moderate. Phenobarbital and Vinblastine 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 P-glycoprotein and may lower vinblastine exposure. This could reduce anticancer efficacy.
How serious is the interaction between Phenobarbital and Vinblastine?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Where possible, use a non-inducing anticonvulsant such as levetiracetam. If phenobarbital is required, monitor for reduced response to vinblastine.
What other medicines interact with Vinblastine?
MediHelp also lists interactions of Vinblastine with, for example, Adenovirus types 4 and 7 live, Apalutamide, Atazanavir. The full list is on the Vinblastine page.
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