Drug interactions
Nefazodone + Ondansetron
Severity: Moderate
Nefazodone and Ondansetron: 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
Nefazodone is a strong CYP3A4 inhibitor and may raise ondansetron exposure, though ondansetron has other metabolic routes. Nefazodone may also contribute to QT prolongation and serotonergic effects.
What this interaction means in plain words
Nefazodone and Ondansetron 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
CYP3A4 inhibition reduces ondansetron clearance, plus possible additive QT and serotonergic effects.
What to do
No fixed dose adjustment is required, but monitor the ECG in patients with QT risk factors. Watch for signs of serotonin toxicity.
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 Ondansetron
- Apomorphine + Ondansetron Contraindicated
- Ondansetron + Thioridazine Contraindicated
- Ondansetron + Vandetanib Contraindicated
- Adagrasib + Ondansetron Major
- Amiodarone + Ondansetron Major
- Amisulpride + Ondansetron Major
Frequently asked questions
Can I take Nefazodone with Ondansetron?
MediHelp rates the interaction as moderate. Nefazodone and Ondansetron 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. Nefazodone is a strong CYP3A4 inhibitor and may raise ondansetron exposure, though ondansetron has other metabolic routes. Nefazodone may also contribute to QT prolongation and serotonergic effects.
How serious is the interaction between Nefazodone and Ondansetron?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: No fixed dose adjustment is required, but monitor the ECG in patients with QT risk factors. Watch for signs of serotonin toxicity.
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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