This medication is used alone or with other medications to prevent nausea and vomiting caused by cancer drug treatment (chemotherapy) and radiation therapy. It is also used to prevent and treat nausea and vomiting after surgery. Ondansetron works by blocking one of the body’s natural substances (serotonin) that causes vomiting.
How to use ondansetron oral
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.
Dosage is based on your medical condition and response to therapy. The dosage for children may also be based on age and weight. In patients with severe liver problems, the usual maximum dose is 8 milligrams in 24 hours. 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.
Inform your doctor if your condition does not improve or if it worsens.
Headache, lightheadedness, dizziness, drowsiness, tiredness, or constipation may occur. If these effects persist or worsen, notify your doctor promptly.
Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.
Tell your doctor right away if you have any serious side effects, including: stomach pain, muscle spasm/stiffness, vision changes (e.g., temporary loss of vision, blurred vision).
Get medical help right away if you have any very serious side effects, including: chest pain, slow/fast/irregular heartbeat, severe dizziness, fainting.
This medication may increase serotonin and rarely cause a very serious condition called serotonin syndrome/toxicity. The risk increases if you are also taking other drugs that increase serotonin, so tell your doctor or pharmacist of all the drugs you take (see Drug Interactions section). Get medical help right away if you develop some of the following symptoms: fast heartbeat, hallucinations, loss of coordination, severe dizziness, severe nausea/vomiting/diarrhea, twitching muscles, unexplained fever, unusual agitation/restlessness.
A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.
This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.