Drug interactions
Phenytoin + Rolapitant
Severity: Moderate
Phenytoin and Rolapitant: 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 is an inducer of CYP3A4 and may lower rolapitant concentrations with chronic use. This could lead to reduced control of delayed nausea and vomiting.
What this interaction means in plain words
Phenytoin and Rolapitant 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 belongs to Central Nervous System; Rolapitant belongs to Gastrointestinal Tract.
Why it happens
Phenytoin induces CYP3A4, accelerating rolapitant clearance.
What to do
Avoid the combination if possible by choosing another antiemetic. If used, monitor for breakthrough emesis.
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 Rolapitant
- Pimozide + Rolapitant Contraindicated
- Rolapitant + Thioridazine Contraindicated
- Atomoxetine + Rolapitant Major
- Deutetrabenazine + Rolapitant Major
- Eliglustat + Rolapitant Major
- Flecainide + Rolapitant Major
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
Frequently asked questions
Can I take Phenytoin with Rolapitant?
MediHelp rates the interaction as moderate. Phenytoin and Rolapitant 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 is an inducer of CYP3A4 and may lower rolapitant concentrations with chronic use. This could lead to reduced control of delayed nausea and vomiting.
How serious is the interaction between Phenytoin and Rolapitant?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Avoid the combination if possible by choosing another antiemetic. If used, monitor for breakthrough emesis.
What other medicines interact with Rolapitant?
MediHelp also lists interactions of Rolapitant with, for example, Pimozide, Thioridazine, Atomoxetine. The full list is on the Rolapitant page.
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