Ondansetron is indicated for the prevention of nausea and vomiting associated with: Ondansetron is also indicated for the prevention of postoperative nausea and/or vomiting. The recommended dosage regimens for adult and pediatric patients are described in Table 1 and Table 2, respectively. These highlights do not include all the information needed to use ONDANSETRON ORALLY DISINTEGRATING TABLETS, safely and effectively. See full prescribing information for ONDANSETRON ORALLY ... Ondansetron is a medicine that blocks the actions of chemicals in the body that can trigger nausea and vomiting. It is used to prevent nausea and vomiting caused by surgery, cancer chemotherapy, or radiation treatment. Learn how to take it, what side effects to watch out for, and what interactions to avoid. Ondansetron Orally Disintegrating Tabs prescription and dosage information for physicians and health care professionals.