Drug interactions
Fedratinib + Phenytoin
Severity: Major
Fedratinib and Phenytoin: major 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
Phenytoin is expected to reduce fedratinib exposure and may lessen its effect in myelofibrosis.
What this interaction means in plain words
Fedratinib and Phenytoin can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for.
Fedratinib belongs to Oncology; Phenytoin belongs to Central Nervous System.
Why it happens
Predicted CYP3A4 induction by phenytoin increases fedratinib clearance.
What to do
Avoid strong CYP3A4 inducers with fedratinib and use a non-inducing antiepileptic. Monitor spleen response and symptoms if unavoidable.
What to ask your pharmacist
- Does the benefit of taking both outweigh the risk in my case?
- Do I need any blood test, ECG or other check while on both?
- What early warning signs should I watch for, and what should I do if they appear?
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Other interactions of Phenytoin
- Artemether / lumefantrine + Phenytoin Contraindicated
- Bictegravir + Phenytoin Contraindicated
- Cabotegravir + Phenytoin Contraindicated
- Doravirine + Phenytoin Contraindicated
- Elbasvir / grazoprevir + Phenytoin Contraindicated
- Elvitegravir / cobicistat / emtricitabine / tenofovir df + Phenytoin Contraindicated
Other interactions of Fedratinib
- Fedratinib + Thioridazine Contraindicated
- Amobarbital + Fedratinib Major
- Apalutamide + Fedratinib Major
- Brexpiprazole + Fedratinib Major
- Carbamazepine + Fedratinib Major
- Chloramphenicol + Fedratinib Major
Frequently asked questions
Can I take Fedratinib with Phenytoin?
MediHelp rates the interaction as major. Fedratinib and Phenytoin can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for. Phenytoin is expected to reduce fedratinib exposure and may lessen its effect in myelofibrosis.
How serious is the interaction between Fedratinib and Phenytoin?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Avoid strong CYP3A4 inducers with fedratinib and use a non-inducing antiepileptic. Monitor spleen response and symptoms if unavoidable.
What other medicines interact with Phenytoin?
MediHelp also lists interactions of Phenytoin with, for example, Artemether / lumefantrine, Bictegravir, Cabotegravir. The full list is on the Phenytoin page.
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