Drug interactions
Perampanel + Phenytoin
Severity: Moderate
Perampanel and Phenytoin: 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
Phenytoin induces CYP3A4 and markedly lowers perampanel concentrations, which may reduce seizure control. Perampanel may also slightly alter phenytoin levels.
What this interaction means in plain words
Perampanel and Phenytoin 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.
Perampanel belongs to Central Nervous System; Phenytoin belongs to Central Nervous System.
Why it happens
CYP3A4 induction by phenytoin increases perampanel clearance.
What to do
Titrate perampanel to clinical response, as higher doses may be needed. Monitor seizure control and perampanel tolerability when phenytoin is started or stopped.
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?
Pro+ members
Unlock the full page
Create an account and start a Pro+ trial to unlock the full management advice for Perampanel and Phenytoin, the additional notes, the evidence detail and the whole-prescription interaction checker.
- Full clinical management advice
- Additional notes
- Evidence detail
- Interaction checker for a whole prescription
Try Pro+ free for 7 days on the web. No card needed.
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 Perampanel
- Apalutamide + Perampanel Major
- Enzalutamide + Perampanel Major
- Alprazolam + Perampanel Moderate
- Amisulpride + Perampanel Moderate
- Amobarbital + Perampanel Moderate
- Asenapine + Perampanel Moderate
Frequently asked questions
Can I take Perampanel with Phenytoin?
MediHelp rates the interaction as moderate. Perampanel and Phenytoin 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. Phenytoin induces CYP3A4 and markedly lowers perampanel concentrations, which may reduce seizure control. Perampanel may also slightly alter phenytoin levels.
How serious is the interaction between Perampanel and Phenytoin?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Titrate perampanel to clinical response, as higher doses may be needed. Monitor seizure control and perampanel tolerability when phenytoin is started or stopped.
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.
Full monographs, dosing and an interaction checker in the MediHelp app
Open the complete reference, check multi-drug interactions and use dosing tools in the MediHelp app.
