The typical maximum amount of Zofran (ondansetron) an adult can take is 24 mg per day. For chemotherapy-induced nausea and vomiting, the dosing varies by emetogenic risk:
- For highly emetogenic chemotherapy, a single 24-mg dose can be given 30 minutes before treatment.
- For moderately emetogenic chemotherapy, 8 mg is taken 30 minutes before treatment, followed by an 8-mg dose 8 hours later, then 8 mg twice daily for 1 to 2 days after chemotherapy.
- For other indications like radiation therapy or postoperative nausea, dosing typically involves 8 mg every 8 hours or as prescribed.
Doses above 24 mg per day are generally not recommended due to increased risk of side effects, including heart rhythm abnormalities. Intravenous doses should not exceed 16 mg per dose due to safety concerns. It's important to follow the prescribing doctor's instructions carefully and not exceed the recommended dose without medical advice.
