Drug interactions
Letermovir + Ondansetron
Severity: Minor
Letermovir 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
Letermovir is a moderate CYP3A inhibitor and may modestly increase ondansetron levels. Since ondansetron has multiple clearance pathways, the effect is generally small.
What this interaction means in plain words
Letermovir 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.
Letermovir belongs to Anti Virals; Ondansetron belongs to Gastrointestinal Tract.
Why it happens
Inhibition of CYP3A4 by letermovir reduces one pathway of ondansetron metabolism.
What to do
No empirical dose adjustment is needed. Monitor for QT-related effects in patients with cardiac risk factors or electrolyte disturbances.
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 Letermovir
- Ergotamine + Letermovir Contraindicated
- Letermovir + Pimozide Contraindicated
- Apalutamide + Letermovir Major
- Atorvastatin + Letermovir Major
- Carbamazepine + Letermovir Major
- Colchicine + Letermovir Major
Frequently asked questions
Can I take Letermovir with Ondansetron?
MediHelp rates the interaction as minor. Letermovir 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. Letermovir is a moderate CYP3A inhibitor and may modestly increase ondansetron levels. Since ondansetron has multiple clearance pathways, the effect is generally small.
How serious is the interaction between Letermovir 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 empirical dose adjustment is needed. Monitor for QT-related effects in patients with cardiac risk factors or electrolyte disturbances.
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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