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Ondansetron

Zofran is the only ondansetron product on this page, a tablet in 4 mg and 8 mg strengths for preventing nausea and vomiting after chemotherapy or surgery.

Zofran

Chemotherapy-induced Nausea and Vomiting

4mg · 8mg

Ondansetron tablets for nausea and vomiting after chemotherapy or surgery. It blocks a chemical that triggers the vomiting reflex.

From$0.56/ tabletView

Key points

  • Do not take ondansetron with apomorphine, a Parkinson’s disease medicine; the combination is a stated contraindication.
  • The label warns against ondansetron in people with congenital long QT syndrome, and calls for ECG monitoring when other QT-prolonging drugs are taken at the same time.
  • Serotonin syndrome has been reported with ondansetron, particularly when taken alongside other serotonergic medicines.

How does Ondansetron work?

Ondansetron blocks 5-HT3 receptors in the gut and the brain’s vomiting centre. When chemotherapy or surgery triggers serotonin release, those receptors send a signal that makes you feel sick and vomit; ondansetron stops that signal from getting through. Because it works specifically on the serotonin pathway, it does not address nausea from other triggers such as motion sickness. Ondansetron is listed under Oncology Support for its role in managing chemotherapy side effects.

Further reading