Drug interactions
Fosphenytoin + Vinorelbine
Severity: Moderate
Fosphenytoin and Vinorelbine: 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
Chemotherapy may lower phenytoin concentrations, risking loss of seizure control. Conversely, phenytoin induces CYP3A4 and may reduce vinorelbine exposure and efficacy.
What this interaction means in plain words
Fosphenytoin and Vinorelbine 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.
Fosphenytoin belongs to Central Nervous System; Vinorelbine belongs to Oncology.
Why it happens
Phenytoin is a CYP3A4 inducer that can lower vinorelbine levels, and chemotherapy may alter phenytoin absorption or disposition.
What to do
Monitor phenytoin levels and seizure control during treatment. Consider a non-enzyme-inducing anticonvulsant such as levetiracetam.
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 Vinorelbine
Other interactions of Fosphenytoin
- Dronedarone + Fosphenytoin Contraindicated
- Fosphenytoin + Ledipasvir-sofosbuvir Contraindicated
- Fosphenytoin + Lorlatinib Contraindicated
- Fosphenytoin + Lurasidone Contraindicated
- Fosphenytoin + Ranolazine Contraindicated
- Fosphenytoin + Sofosbuvir-velpatasvir-voxilaprevir Contraindicated
Frequently asked questions
Can I take Fosphenytoin with Vinorelbine?
MediHelp rates the interaction as moderate. Fosphenytoin and Vinorelbine 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. Chemotherapy may lower phenytoin concentrations, risking loss of seizure control. Conversely, phenytoin induces CYP3A4 and may reduce vinorelbine exposure and efficacy.
How serious is the interaction between Fosphenytoin and Vinorelbine?
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 phenytoin levels and seizure control during treatment. Consider a non-enzyme-inducing anticonvulsant such as levetiracetam.
What other medicines interact with Vinorelbine?
MediHelp also lists interactions of Vinorelbine with, for example, Adenovirus types 4 and 7 live, Apalutamide, Belatacept. The full list is on the Vinorelbine page.
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