Drug interactions
Ethotoin + Methadone
Severity: Moderate
Ethotoin and Methadone: 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
Hydantoin anticonvulsants induce hepatic enzymes, and phenytoin is known to lower methadone levels and precipitate withdrawal. Ethotoin is a related hydantoin and may have a similar though less documented effect.
What this interaction means in plain words
Ethotoin and Methadone 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.
Why it happens
Probable induction of CYP-mediated methadone metabolism by the hydantoin, extrapolated from phenytoin.
What to do
Monitor for opioid withdrawal and reduced analgesia when ethotoin is started, and raise the methadone dose as needed. Watch for toxicity if ethotoin is 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 Ethotoin and Methadone, 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 Methadone
- Alvimopan + Methadone Contraindicated
- Calcium / magnesium / potassium / sodium oxybates + Methadone Contraindicated
- Droperidol + Methadone Contraindicated
- Ibutilide + Methadone Contraindicated
- Isocarboxazid + Methadone Contraindicated
- Lefamulin + Methadone Contraindicated
Frequently asked questions
Can I take Ethotoin with Methadone?
MediHelp rates the interaction as moderate. Ethotoin and Methadone 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. Hydantoin anticonvulsants induce hepatic enzymes, and phenytoin is known to lower methadone levels and precipitate withdrawal. Ethotoin is a related hydantoin and may have a similar though less documented effect.
How serious is the interaction between Ethotoin and Methadone?
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 for opioid withdrawal and reduced analgesia when ethotoin is started, and raise the methadone dose as needed. Watch for toxicity if ethotoin is stopped.
What other medicines interact with Methadone?
MediHelp also lists interactions of Methadone with, for example, Alvimopan, Calcium / magnesium / potassium / sodium oxybates, Droperidol. The full list is on the Methadone 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.
