Zofran (ondansetron) is typically taken 2 to 3 times a day, with doses spaced about 8 hours apart. For example, the usual adult dose is 8 mg every 8 to 12 hours. It is sometimes given more frequently initially (such as every 4 to 6 hours) depending on the condition being treated, but the maximum daily dose should not be exceeded, and long-term use should be guided by a healthcare provider. After chemotherapy or radiation treatment, Zofran is often taken for 1 to 2 days. It can be taken with or without food, and if used for nausea related to meals, some forms should be taken 15 to 60 minutes before eating. Frequent dosing more than every 8 hours increases risks of side effects like constipation, headache, or heart electrical rhythm changes, so following the prescribed schedule is important.
