Drug interactions
Phenytoin + Ubrogepant
Severity: Major
Phenytoin and Ubrogepant: major interaction.
Last updated Sources: Health Canada product monograph
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 may greatly reduce ubrogepant exposure, leading to loss of acute migraine relief.
What this interaction means in plain words
Phenytoin and Ubrogepant 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 belongs to Central Nervous System; Ubrogepant belongs to Central Nervous System.
Why it happens
Phenytoin induces CYP3A4, the main enzyme metabolizing ubrogepant.
What to do
Avoid concomitant use and select a different acute migraine therapy not dependent on CYP3A4. Monitor response if it must be combined.
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?
Pro+ members
Unlock the full page
Create an account and start a Pro+ trial to unlock the full management advice for Phenytoin and Ubrogepant, 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.
References
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 Ubrogepant
- Clarithromycin + Ubrogepant Contraindicated
- Itraconazole + Ubrogepant Contraindicated
- Ketoconazole + Ubrogepant Contraindicated
- Posaconazole + Ubrogepant Contraindicated
- Ubrogepant + Voriconazole Contraindicated
- Apalutamide + Ubrogepant Major
Frequently asked questions
Can I take Phenytoin with Ubrogepant?
MediHelp rates the interaction as major. Phenytoin and Ubrogepant 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 may greatly reduce ubrogepant exposure, leading to loss of acute migraine relief.
How serious is the interaction between Phenytoin and Ubrogepant?
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 concomitant use and select a different acute migraine therapy not dependent on CYP3A4. Monitor response if it must be combined.
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.
