Drug interactions
Ondansetron + Valbenazine
Severity: Moderate
Ondansetron and Valbenazine: 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
Valbenazine can cause dose-related QT prolongation at higher exposures, and ondansetron also prolongs QT. Combined use may increase the risk of arrhythmia in susceptible patients.
What this interaction means in plain words
Ondansetron and Valbenazine 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.
Ondansetron belongs to Gastrointestinal Tract; Valbenazine belongs to Central Nervous System.
Why it happens
Additive QT prolongation.
What to do
Monitor ECG in patients with cardiac risk factors and correct electrolyte abnormalities. Use an alternative antiemetic if QTc prolongs.
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
Other interactions of Valbenazine
- Deutetrabenazine + Valbenazine Contraindicated
- Tranylcypromine + Valbenazine Contraindicated
- Amiodarone + Valbenazine Major
- Amisulpride + Valbenazine Major
- Apalutamide + Valbenazine Major
- Carbamazepine + Valbenazine Major
Frequently asked questions
Can I take Ondansetron with Valbenazine?
MediHelp rates the interaction as moderate. Ondansetron and Valbenazine 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. Valbenazine can cause dose-related QT prolongation at higher exposures, and ondansetron also prolongs QT. Combined use may increase the risk of arrhythmia in susceptible patients.
How serious is the interaction between Ondansetron and Valbenazine?
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 ECG in patients with cardiac risk factors and correct electrolyte abnormalities. Use an alternative antiemetic if QTc prolongs.
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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