Ondansetron is an Antiemetic prescribed for nausea and vomiting. Antiemetics treat motion sickness, chemotherapy-induced nausea and vomiting, and the side effects of general anesthetics and opioid analgesics.
Few medicines act on the chemoreceptor trigger zone-CTZ (in the brain) by preventing the stimulation. The chemoreceptor trigger zone is a vomiting center. Some medications act as prokinetic agents by speeding up the rate at which the stomach empties.
Classification of Antiemetics:
- 5-HT3 receptor antagonists: Ondansetron, Granisetron, Dolasetron, etc.
- Dopamine D2-receptor antagonists act in the brain:Domperidone, Metoclopramide, Mosapride, etc.
- Antihistamines or H1- histamine receptor antagonists:Diphenhydramine, Promethazine, etc.
- Benzodiazepines: Midazolam, Lorazepam, etc.
- Anticholinergics: Scopolamine, Hyoscine, Dicyclomineetc.
- Steroids: Dexamethasone etc.
| Parameters | Description |
|---|---|
| Category of Drug | 5-HT3 receptor antagonists |
| Structure 1 |  |
| IUPAC Name 1 | 9-methyl-3-[(2-methylimidazol-1-yl)methyl]-2,3-dihydro-1H-carbazol-4-one |
| Molecular details | molecular weight- 293.4 g/mol molecular formula- C18H19N3O |
| Mechanism of Action | Ondansetron is an Antiemetic prescribed for nausea and vomiting. |
| Indications | Ondansetron is used for 1. Postoperative nausea and vomiting 2. Chemotherapy and/or radiotherapy-induced nausea and vomiting. |
| Pharmacokinetic properties 5 | 1. Absorption- absorbed from the gastrointestinal tract; approximately 56% to 60% 2. The volume of distribution – 160L 3. the plasma protein binding -73% 4. extensively metabolized and excreted in the urine and feces 5. Half-life- approximately 3-4 hours and could be extended to 6-8 hours |
| Well Known Pharmaceutical Brands | 1. ONDEM- ALKEM 2. EMESET-CIPLA 3. VOMIKIND-MANKIND 4. PERISET-IPCA LABS 5. ZOFER-SUN 6. EMIGO-EMCURE |
| Available dosage forms | 1. TABLETS 2. INJECTION 3. DROPS 4. SUSPENSION  |
| Dose | Adult- 10 to 20 mg 3 to 4 times a day Child- 0.3 to 0.6 mg/kg TDS. |
| Storage conditions | Store protected from light and moisture. |
| Contraindications | Hypersensitivity |
| Precautions | 1. Moderate to severe liver impairment 2. Pregnancy 3. lactation 4. Hypersensitivity to other selective 5-HT3 receptor antagonists 5. Subacute intestinal obstruction 6. Cardiac disease 7. Electrolyte abnormalities 8. QT interval prolongation |
| Adverse Effects | 1. Headache 2. Constipation or diarrhoea 3. Dizziness 4. Flushing 5. Hypersensitivity reaction 6. Anaphylaxis/anaphylactoid reactions 7. Angioedema 8. Bronchospasm 9. Hypotension 10. Laryngeal edema 11. Urticaria |
| Pregnancy Category | B |
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