Drug interactions
Ethotoin + Lamotrigine
Severity: Moderate
Ethotoin and Lamotrigine: 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 related to phenytoin, which strongly lowers lamotrigine concentrations. A similar but less well characterized effect may occur and could reduce seizure control.
What this interaction means in plain words
Ethotoin and Lamotrigine 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 lamotrigine glucuronidation by ethotoin, extrapolated from phenytoin.
What to do
Monitor seizure control or lamotrigine levels and raise the lamotrigine dose if needed. Reduce the dose again if ethotoin is withdrawn.
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 Lamotrigine
Frequently asked questions
Can I take Ethotoin with Lamotrigine?
MediHelp rates the interaction as moderate. Ethotoin and Lamotrigine 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 related to phenytoin, which strongly lowers lamotrigine concentrations. A similar but less well characterized effect may occur and could reduce seizure control.
How serious is the interaction between Ethotoin and Lamotrigine?
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 seizure control or lamotrigine levels and raise the lamotrigine dose if needed. Reduce the dose again if ethotoin is withdrawn.
What other medicines interact with Lamotrigine?
MediHelp also lists interactions of Lamotrigine with, for example, Desogestrel-ethinyl estradiol, Divalproex, Dofetilide. The full list is on the Lamotrigine page.
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