Ondansetron Dosing Guidelines

Dosing Recommendations

The American Society of Clinical Oncology recommends 8 mg of ondansetron orally every 8-12 hours, with a maximum of 24 mg per day, for adults as a PRN medication 1, 2, 3
For intravenous administration, the standard dose is 8 mg or 0.15 mg/kg, with a slow IV push over 2-5 minutes 1, 2, 4

For high emetogenic risk, 8 mg oral twice daily or 8 mg IV is recommended 1, 4
For moderate emetogenic risk, 8 mg oral twice daily or 8 mg IV is recommended 1, 3
For low emetogenic risk, 8 mg oral or IV as needed is recommended 2, 3
For high risk radiation, 8 mg oral or IV before treatment is recommended 2, 5
For moderate risk radiation, 8 mg oral or IV before treatment is recommended 2, 5
For low risk radiation, 8 mg oral or IV as breakthrough therapy is recommended 3, 5

To manage constipation, ensure adequate hydration and consider prophylactic stool softeners 6