Does Ondansetron Interact with Amiodarone?
CDI records a major classification for Ondansetron and Amiodarone. The stored summary is: Both ondansetron and amiodarone prolong the QT interval; used together they raise the risk of QT prolongation and torsades de pointes. Avoid the combination in patients with additional QT risk factors (electrolyte disturbance, bradycardia, other QT-prolonging drugs). The mechanism involves additive blockade of the cardiac herg (ikr) potassium channel prolongs ventricular repolarization. Patients taking both medications should consult their healthcare provider before starting, stopping, or changing the dosage of either drug. This information is drawn from established clinical references and is provided alongside our FDA-labeling–based data. The summary and severity classification are CDI's processed information, not a verbatim source quotation. Product, route, and patient circumstances matter.
Evidence status
A current label comparison is not yet available for this record. The summary and severity are stored CDI information; they have not been independently validated on this page against the exact product label.
Confirm the medicine, formulation, route, and applicable warning with your pharmacist or prescriber. Independent clinical review has not been recorded.
- Stored CDI classification
- Major
- Ondansetron Class
- Serotonin-3 Receptor Antagonist
- Management
- Confirm exact products with your pharmacist
- Data Source
- Curated clinical reference
Recorded Mechanism
Additive blockade of the cardiac hERG (IKr) potassium channel prolongs ventricular repolarization.
What To Tell Your Doctor or Pharmacist
If you are taking Ondansetron and your doctor is considering prescribing Amiodarone (or vice versa), make sure to:
- Inform your doctor and pharmacist of all current medications, including over-the-counter drugs and supplements
- Ask whether the benefits of combining these medications outweigh the risks for your specific situation
- Ask what symptoms to watch for that would indicate the interaction is causing problems
- Ask how frequently you should be monitored while these are co-prescribed
- Ask whether any dosage adjustments are needed
- Never stop or change either medication without first consulting your healthcare provider