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Zofran (ondansetron)
Selective 5-HT3 receptor antagonist that blocks serotonin-mediated nausea and vomiting signals in the CTZ and vagal afferents.
Ondansetron (Zofran) is the most prescribed antiemetic, developed by Glaxo and approved in 1991. It revolutionized management of chemotherapy-induced nausea. The ODT formulation is widely used in emergency departments and pediatrics. Available generically.
At a glance
| Generic name | ondansetron |
|---|---|
| Also known as | Zofran |
| Sponsor | GSK (originally Glaxo) |
| Drug class | 5-HT3 receptor antagonist (antiemetic) |
| Target | Aldehyde oxidase, 5-hydroxytryptamine receptor 3B, Multidrug and toxin extrusion protein 1 |
| Modality | Small molecule |
| Therapeutic area | Gastroenterology |
| Phase | FDA-approved |
| First approval | 1991-01-04 (United States) |
Mechanism of action
Ondansetron revolutionized the management of chemotherapy-induced nausea and vomiting (CINV) when it was introduced. It selectively blocks 5-HT3 receptors both in the chemoreceptor trigger zone (CTZ) and on vagal afferents in the GI tract. Now widely used for postoperative nausea, radiation-induced emesis, and gastroenteritis-related vomiting. The orally disintegrating tablet (ODT) is particularly useful for patients who cannot swallow.
Approved indications
- Chemotherapy-induced nausea and vomiting
- Prevention of Post-Operative Nausea and Vomiting
- Prevention of Radiation-Induced Nausea and Vomiting
Common side effects
- Headache
- Diarrhea
- Drowsiness/Sedation
- Fever
- Constipation
- Injection-site reaction
- Pruritus
- Paresthesia
- Cold sensation
- Transient transaminase elevation
- Rash
Serious adverse events
- Grand mal seizure
- Extrapyramidal reactions
- Angina (chest pain)
- Electrocardiographic alterations
- Hypotension
- Tachycardia
- Hypokalemia
Key clinical trials
- Comparative Clinical Study Among Ondansetron and Gabapentin in Preventing Postoperative Nausea and Vomiting After Laparoscopic Sleeve Gastrectomy (Phase 3)
- An Open Label Phase II Study of Aprepitant for Multi-day Moderately-high to Highly Emetogenic Chemotherapy Regimens (Phase 2)
- An Open-label, Randomised Study Comparing the Uptake of rIL-2 in HIV-1 Infected Individuals Receiving Different Combinations of Antiemetics and Analgesic Agents During rIL-2 Dosing in ESPRIT: Toxicity (Phase 3)
- Comparing the Effects of Ondansetron Versus Dexamethasone on the Incidence of Post-dural Puncture Headache (PDPH) , Nausea and Vomiting After Spinal Anaesthesia of Parturients Undergoing Caesarean Sec (Phase 4)
- Optimizing Anesthesia Antiemetic Measures Versus Combination With Dexamethasone or Ondansetron in the Prevention of Postoperative Nausea and Vomiting. (Phase 4)
- Double Blinded Study Ondansetron's Opposite Effect on Postoperative Analgesia of Acetaminophen (Phase 4)
- Ondanstron Weekly vs Every 3 Weeks for Prevention of Nausea and Vomiting Induced by Chemotherapy Combined With PD-1 Blockade：an Randomized Clinical Trial (NA)
- Preoperative Point of Care Ultrasound Guided Fluid Optimization and Intravenous Ondansetron to Prevent General Anesthesia-Induced Hypotension: A Randomized Controlled Trial (NA)
Patents
| Patent | Expiry | Type |
|---|---|---|
| 9095577 | 2030-07-13 | Formulation |
| 8580830 | 2029-11-23 | Formulation |
Primary sources
Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.
| Source | Used for |
|---|---|
| FDA label | Mechanism, indications, dosing, boxed warnings, drug interactions |
| ClinicalTrials.gov | Trial enrolment, design, endpoints, results |
| FDA Orange Book | Patents + exclusivity |