Drug interactions
Mexiletine + Ondansetron
Severity: Minor
Mexiletine and Ondansetron: minor 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
Mexiletine inhibits CYP1A2, one of several enzymes that clear ondansetron, so ondansetron exposure could rise slightly. Because ondansetron is cleared by multiple pathways, the clinical effect is expected to be small.
What this interaction means in plain words
Mexiletine and Ondansetron have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised.
Mexiletine belongs to Cardiovascular; Ondansetron belongs to Gastrointestinal Tract.
Why it happens
Mexiletine inhibits CYP1A2-mediated metabolism of ondansetron, which is only one of several elimination routes.
What to do
No dose adjustment is needed. Be aware of additive QT effects if other QT-prolonging drugs are given and check an ECG where risk factors exist.
What to ask your pharmacist
- Is there anything I should notice while taking both?
- Do I need to tell my doctor at the next visit?
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Other interactions of Ondansetron
- Apomorphine + Ondansetron Contraindicated
- Ondansetron + Thioridazine Contraindicated
- Ondansetron + Vandetanib Contraindicated
- Adagrasib + Ondansetron Major
- Amiodarone + Ondansetron Major
- Amisulpride + Ondansetron Major
Other interactions of Mexiletine
- Fezolinetant + Mexiletine Contraindicated
- Mexiletine + Pimozide Contraindicated
- Alosetron + Mexiletine Major
- Amiodarone + Mexiletine Major
- Clozapine + Mexiletine Major
- Cobicistat + Mexiletine Major
Frequently asked questions
Can I take Mexiletine with Ondansetron?
MediHelp rates the interaction as minor. Mexiletine and Ondansetron have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised. Mexiletine inhibits CYP1A2, one of several enzymes that clear ondansetron, so ondansetron exposure could rise slightly. Because ondansetron is cleared by multiple pathways, the clinical effect is expected to be small.
How serious is the interaction between Mexiletine and Ondansetron?
MediHelp rates it minor, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: No dose adjustment is needed. Be aware of additive QT effects if other QT-prolonging drugs are given and check an ECG where risk factors exist.
What other medicines interact with Ondansetron?
MediHelp also lists interactions of Ondansetron with, for example, Apomorphine, Thioridazine, Vandetanib. The full list is on the Ondansetron page.
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