Drug interactions
Phenobarbital + Vincristine
Severity: Moderate
Phenobarbital and Vincristine: 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-gp, which can increase vincristine clearance. Enzyme-inducing anticonvulsants have been associated with lower vincristine exposure and possibly reduced efficacy.
What this interaction means in plain words
Phenobarbital and Vincristine 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-gp, increasing vincristine elimination.
What to do
Prefer a non-enzyme-inducing anticonvulsant such as levetiracetam where seizure control allows. Otherwise monitor treatment response.
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 Vincristine
- Adenovirus types 4 and 7 live + Vincristine Contraindicated
- Apalutamide + Vincristine Major
- Atazanavir + Vincristine Major
- Ceritinib + Vincristine Major
- Chloramphenicol + Vincristine Major
- Clarithromycin + Vincristine Major
Frequently asked questions
Can I take Phenobarbital with Vincristine?
MediHelp rates the interaction as moderate. Phenobarbital and Vincristine 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-gp, which can increase vincristine clearance. Enzyme-inducing anticonvulsants have been associated with lower vincristine exposure and possibly reduced efficacy.
How serious is the interaction between Phenobarbital and Vincristine?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Prefer a non-enzyme-inducing anticonvulsant such as levetiracetam where seizure control allows. Otherwise monitor treatment response.
What other medicines interact with Vincristine?
MediHelp also lists interactions of Vincristine with, for example, Adenovirus types 4 and 7 live, Apalutamide, Atazanavir. The full list is on the Vincristine page.
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