Drug interactions
Mexiletine + Primidone
Severity: Moderate
Mexiletine and Primidone: 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
Primidone is metabolized to phenobarbital and induces hepatic enzymes, which may lower mexiletine concentrations. This can reduce therapeutic effect.
What this interaction means in plain words
Mexiletine and Primidone 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.
Mexiletine belongs to Cardiovascular; Primidone belongs to Central Nervous System.
Why it happens
Enzyme induction by primidone and phenobarbital increases mexiletine clearance.
What to do
Monitor clinical response and mexiletine levels, and raise the dose if efficacy declines. Reassess when primidone 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?
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Other interactions of Mexiletine
- Fezolinetant + Mexiletine Contraindicated
- Mexiletine + Pimozide Contraindicated
- Alosetron + Mexiletine Major
- Amiodarone + Mexiletine Major
- Clozapine + Mexiletine Major
- Cobicistat + Mexiletine Major
Other interactions of Primidone
- Lorlatinib + Primidone Contraindicated
- Lurasidone + Primidone Contraindicated
- Primidone + Ranolazine Contraindicated
- Primidone + Sofosbuvir-velpatasvir-voxilaprevir Contraindicated
- Primidone + Voriconazole Contraindicated
- Abiraterone + Primidone Major
Frequently asked questions
Can I take Mexiletine with Primidone?
MediHelp rates the interaction as moderate. Mexiletine and Primidone 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. Primidone is metabolized to phenobarbital and induces hepatic enzymes, which may lower mexiletine concentrations. This can reduce therapeutic effect.
How serious is the interaction between Mexiletine and Primidone?
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 clinical response and mexiletine levels, and raise the dose if efficacy declines. Reassess when primidone is stopped.
What other medicines interact with Mexiletine?
MediHelp also lists interactions of Mexiletine with, for example, Fezolinetant, Pimozide, Alosetron. The full list is on the Mexiletine page.
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