It is used alone or with other medications to prevent nausea and vomitingcaused by cancer drug treatment (chemotherapy) and radiation therapy.

Headache, lightheadedness, dizziness, drowsiness, tiredness, or constipation may occur.

It is contraindiacted in patients with known hypersensitivity to the drug.

Before taking ondansetron, tell your doctor or pharmacist if you are allergic to it; or to other anti-nausea serotonin blockers (e.g., granisetron); or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

Take this medication exactly as directed. Do not take more medication or take it more often than prescribed. Ask your doctor or pharmacist if you have questions.

Before using this medication, tell your doctor or pharmacist your medical history, especially of: irregular heartbeat, liver disease, stomach/intestinal problems (e.g., recent abdominal surgery, ileus, swelling).

Do not drive, use machinery, or do anything that needs alertness until you can do it safely

Please consult your doctor when taking this medicine if you are pregnant.

Products that may interact with this drug are Dofetilide, pimozide, procainamide, amiodarone, quinidine, sotalol, macrolide antibiotics (such as erythromycin)