Drug interactions
Ethotoin + Fentanyl
Severity: Moderate
Ethotoin and Fentanyl: 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
Ethotoin is a hydantoin anticonvulsant that can cause drowsiness and dizziness, adding to fentanyl sedation. As a hydantoin it may also induce CYP3A4 like phenytoin, potentially lowering fentanyl levels.
What this interaction means in plain words
Ethotoin and Fentanyl 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
Additive CNS depression, with possible CYP3A4 induction reducing fentanyl exposure.
What to do
Monitor for sedation and for reduced analgesic effect, and adjust the fentanyl dose to response.
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 Fentanyl
- Alvimopan + Fentanyl Contraindicated
- Fentanyl + Isocarboxazid Contraindicated
- Fentanyl + Olanzapine / samidorphan Contraindicated
- Fentanyl + Phenelzine Contraindicated
- Fentanyl + Tranylcypromine Contraindicated
- Alfentanil + Fentanyl Major
Frequently asked questions
Can I take Ethotoin with Fentanyl?
MediHelp rates the interaction as moderate. Ethotoin and Fentanyl 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. Ethotoin is a hydantoin anticonvulsant that can cause drowsiness and dizziness, adding to fentanyl sedation. As a hydantoin it may also induce CYP3A4 like phenytoin, potentially lowering fentanyl levels.
How serious is the interaction between Ethotoin and Fentanyl?
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 sedation and for reduced analgesic effect, and adjust the fentanyl dose to response.
What other medicines interact with Fentanyl?
MediHelp also lists interactions of Fentanyl with, for example, Alvimopan, Isocarboxazid, Olanzapine / samidorphan. The full list is on the Fentanyl page.
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