This page contains brief details about the drug , it's indication, dosage & administaration, mechanism of action, related brands with strength, warnings and common side effects.

Background and Date of Approval

Ondansetron was first developed in England and approved for medical use by the FDA in 1991 to treat nausea and vomiting.

Mechanism of Action of undefined

Ondansetron may work by blocking 5-HT3 receptors peripherally on vagal nerve terminals and centrally in the chemoreceptor trigger zone. It works by blocking the action of serotonin, a natural substance that may cause nausea and vomiting. 

Uses of undefined

Ondansetron is used to treat nausea and vomiting in patients which is caused by some treatments such as chemotherapy or radiotherapy for cancer and nausea and vomiting that occurs post-surgery. 

undefined Drug administaration and Dosage available

Ondansetron is available in two different forms of injectable solution [IV] and oral tablets. Tablets are available in various different strengths: oral tablets - 4mg, 8 mg, 24mg. Oral disintegrating tablets- 4 mg, 8 mg, 24 mg. Your physician will decide the dosage of this injection based on the severity of your disease and other factors.

Warnings, Precautions and Side Effects of undefined


It is not recommended to take ondansetron if you are allergic to ondansetron or any of its ingredients. It is also not recommended for children. Inform your doctor if you have any neurological, heart, liver, lung, or kidney problems before getting treated with ondansetron. It must be avoided in patients with prolonged QT interval. Ondansetron may increase the risk of serotonin syndrome when used in combination with other serotonergic medications, such as certain antidepressants. Always get a detailed overview of your medical history and the medication from your doctor before starting the treatment. 


Before receiving ondansetron in any available forms, inform your doctor if you are pregnant, planning pregnancy, or breastfeeding. The medication will be administered as needed, and it is crucial to consult your doctor for personalized guidance. If you have liver disorders, disclose them to your physician as the dosage must be adjusted. 

Side Effects

Ondansetron, like many medications, can lead to side effects. It may cause common side effects such as Constipation, diarrhoea, Headache, Hypoxia, General tiredness or weakness However not everyone experiences these effects, but if you do, promptly inform your healthcare provider for guidance.

Word Of Advice

If you forgot to receive the injection, contact your healthcare professional and reschedule it as soon as you remember. Inform your physician immediately if you face any allergic reactions such as sudden wheezing and chest pain or tightness, swelling of the eyelids, face, lips, mouth, tongue, difficulty breathing, skin rashes, or temporary loss of vision after receiving this medicine. Do not stop taking this medicine unless your doctor tells you to. Your doctor will regularly do lab tests to check the effectiveness of the medicine. 

Frequently Asked Question


  1. Aurobindo Pharma (Malta) Limited, Electronic Medicines Compendium (EMC), [Revised on January 2023] [Accessed on June 2023],
  2. GlaxoSmithKline, US Food & Drug Administration, [Revised on January 2023] [Accessed on June 2023],
  3. Kenneth R. McQuaid, Drugs Used in the Treatment of Gastrointestinal Diseases, Lange’s Basic and Clinical Pharmacology, 14th Edition, 2018, 1087-1119


The drug information on this page is not a substitute for medical advice. It is meant for educational purposes only. For further details, consult your doctor about your medical condition to know if you can receive this treatment.