Ondansetron

Ondansetron, sold under the brand name Zofran among others, is a medication used to prevent nausea and vomiting caused by chemotherapy, radiation therapy, migraines, or surgery. It is also effective for treating gastroenteritis. It can be given orally (by mouth), intramuscularly (injection into a muscle), or intravenously (injection into a vein). Common side effects include diarrhea, constipation, headache, sleepiness, and itchiness. Serious side effects include QT prolongation and severe allergic reaction. It appears to be safe during pregnancy but has not been well studied in this group. It is a serotonin 5-HT3 receptor antagonist. It does not have any effect on dopamine receptors or muscarinic acetylcholine receptor and therefore does not cause akathisia. Ondansetron was patented in 1984 and approved for medical use in 1990. It is on the World Health Organization's List of Essential Medicines. It is available as a generic medication. In 2023, it was the 53rd most commonly prescribed medication in the United States, with more than 12 million prescriptions.