Drug interactions
Ondansetron + Sotalol
Severity: Major
Ondansetron and Sotalol: major 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
Sotalol is a class III antiarrhythmic with a well-established risk of QT prolongation and torsades de pointes. Adding ondansetron increases that risk, so the combination should be avoided where possible.
What this interaction means in plain words
Ondansetron and Sotalol can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for.
Ondansetron belongs to Gastrointestinal Tract; Sotalol belongs to Cardiovascular.
Why it happens
Additive potassium channel blockade and delayed ventricular repolarization; sotalol also causes bradycardia.
What to do
Avoid the combination and use an antiemetic with less QT effect. If it cannot be avoided, correct electrolytes and monitor the ECG.
What to ask your pharmacist
- Does the benefit of taking both outweigh the risk in my case?
- Do I need any blood test, ECG or other check while on both?
- What early warning signs should I watch for, and what should I do if they appear?
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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 Sotalol
- Arsenic trioxide + Sotalol Contraindicated
- Artemether / lumefantrine + Sotalol Contraindicated
- Disopyramide + Sotalol Contraindicated
- Dofetilide + Sotalol Contraindicated
- Dronedarone + Sotalol Contraindicated
- Droperidol + Sotalol Contraindicated
Frequently asked questions
Can I take Ondansetron with Sotalol?
MediHelp rates the interaction as major. Ondansetron and Sotalol can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for. Sotalol is a class III antiarrhythmic with a well-established risk of QT prolongation and torsades de pointes. Adding ondansetron increases that risk, so the combination should be avoided where possible.
How serious is the interaction between Ondansetron and Sotalol?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Avoid the combination and use an antiemetic with less QT effect. If it cannot be avoided, correct electrolytes and monitor the ECG.
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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