Because ondansetron ODT is an orally disintegrating tablet, it should be placed on the top of the tongue and dissolved with saliva, rather than swallowed whole.
Adults with cancer are typically given 24 mg 30 minutes before the start of chemotherapy. Additional doses are sometimes given after the chemotherapy if needed.
For more moderate post-chemotherapy nausea and vomiting, 8 mg is given 30 minutes before starting cancer treatment. The 8 mg dose is taken again 8 hours after the first dose. Then, the dose is 8 mg every 12 hours for 1 to 2 days.
Patients undergoing radiotherapy are typically given 8 mg 1-2 hours before radiotherapy.
Patients undergoing surgery are typically given 16 mg 1 hour before receiving anesthesia.