This medication is dissolved on top of the tongue. It is not meant to be chewed or swallowed like other tablet forms.

Dry your hands before using this medication. This medication may come in a bottle or a blister pack. If using the blister pack, peel back the foil on the blister pack to remove a tablet. Do not push the tablet through the foil. Immediately after removing the tablet, place it on the tongue. Allow it to dissolve completely, then swallow it with saliva. You do not need to take this product with water. Doing so may increase your chance of getting a headache.

To prevent nausea from chemotherapy, take this medication usually within 30 minutes before treatment begins. To prevent nausea from radiation treatment, take this medication 1 to 2 hours before the start of your treatment. To prevent nausea after surgery, take ondansetron 1 hour before the start of surgery. This medication may be taken with or without food. However, your doctor may tell you not to eat before chemotherapy, radiation, or surgery.

Take any other doses as directed by your doctor. Ondansetron may be taken up to 3 times a day for 1 to 2 days after your chemotherapy or radiation treatment is finished. If you are taking this medication on a prescribed schedule, take it regularly in order to get the most benefit from it. To help you remember, take it at the same times each day.

The dosage is based on your medical condition and response to treatment. Children's dosage may also be based on age and weight. 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.

Tell your doctor if your condition does not get better or if it gets worse.