Erythromycin and Ondansetron: Drug Interaction Guide
Quick answer: This is a major interaction — avoid combining Erythromycin and Ondansetron unless specifically directed by your doctor.
How Erythromycin interacts with Ondansetron
Both drugs inhibit cardiac repolarizing potassium currents and prolong the QT interval, increasing the risk of torsades de pointes.
What you should do
Avoid the combination when possible, especially in patients with cardiac disease, bradycardia, electrolyte abnormalities, or other QT-prolonging medicines.
Key facts
Severity
Major — avoid combination
Mechanism
Both drugs inhibit cardiac repolarizing potassium currents and prolong the QT interval, increasing the risk of torsades ...
Action
Avoid the combination when possible, especially in patients with cardiac disease, bradycardia, electrolyte abnormalities...
Frequently asked questions
Can I take Erythromycin and Ondansetron together?
No — this combination should generally be avoided. Avoid the combination when possible, especially in patients with cardiac disease, bradycardia, electrolyte abnormalities, or other QT-prolonging medicines.
What is the severity of this interaction?
The interaction between Erythromycin and Ondansetron is classified as Major — avoid combination. Both drugs inhibit cardiac repolarizing potassium currents and prolong the QT interval, increasing the risk of torsades de pointes.
What should I do if I'm prescribed both?
Avoid the combination when possible, especially in patients with cardiac disease, bradycardia, electrolyte abnormalities, or other QT-prolonging medicines. Always consult your prescribing clinician — do not stop or change medications without medical guidance.
Last reviewed: by iMedic Medical Editorial Team. Our editorial process.