Ondansetron

Indications
Oral
Prophylaxis of postoperative nausea and vomiting
Adult: 16 mg taken 1 hr before anaesthesia; or 8 mg taken 1 hr before anaesthesia followed by 2 more doses of 8 mg at 8-hr intervals.
Hepatic impairment: Moderate or severe hepatic impairment: Max: 8 mg daily.
Oral
Nausea and vomiting associated with cancer chemotherapy
Adult: 24 mg, as a single dose, 30 minutes before the start of single-day chemotherapy.
Child: 4-11 yr: 4 mg 30 minutes before chemotherapy; repeat dose at 4 and 8 hr after initial dose, then 4 mg every 8 hr for 1-2 days after completion of chemotherapy.
Hepatic impairment: Moderate or severe hepatic impairment: Max: 8 mg daily.
Oral
Nausea and vomiting associated with cancer chemotherapy or radiotherapy
Adult: For less emetogenic chemotherapy and/or radiotherapy: 8 mg 2 hr before treatment followed by 8 mg 8-12 hr later.
Hepatic impairment: Moderate or severe hepatic impairment: Max: 8 mg daily.
Oral
Prevent delayed emesis following chemotherapy
Adult: 8 mg bid, for up to 5 days after the end of a course of chemotherapy.
Hepatic impairment: Moderate or severe hepatic impairment: Max: 8 mg daily.
Parenteral
Nausea and vomiting associated with cancer chemotherapy
Adult: For highly emetogenic chemotherapy: 8 mg as a single dose, given via IM or slow IV inj immediately before treatment; or 8 mg IM or slow IV inj given immediately before treatment followed by either continuous IV infusion of 1 mg/hr for up to 24 hr or by a further 2 doses of 8 mg 2-4 hr apart; or 32 mg as a single dose via IV infusion over ≥15 minutes immediately before treatment; or 150 mcg/kg via IV infusion over 15 minutes (beginning 30 minutes before chemotherapy) and repeated 4 and 8 hr after the 1st dose. Anti-emetic efficacy can be enhanced by giving 20 mg dexamethasone sodium phosphate via IV admin before chemotherapy.
Child: ≥6 mth: 150 mcg/kg via IV infusion 30 minutes before the start of chemotherapy, repeat dose at 4 and 8 hr after the first dose; or 0.45 mg/kg/day as a single dose.
Hepatic impairment: Moderate or severe hepatic impairment: Max: 8 mg daily.
Parenteral
Prophylaxis of postoperative nausea and vomiting
Adult: 4 mg as a single dose via IM or slow IV inj at induction of anaesthesia.
Child: ≥1 mth: ≤40 kg: 100 mcg/kg as a single dose; >40 kg: 4 mg as a single dose.
Max Dosage: Child: 4 mg.
Hepatic impairment: Moderate or severe hepatic impairment: Max: 8 mg daily.
Parenteral
Postoperative nausea and vomiting
Adult: 4 mg IM or slow IV inj as a single dose.
Child: ≥1 mth: 100 mcg/kg slow IV injection, up to a maximum of 4 mg.
Hepatic impairment: Moderate or severe hepatic impairment: Max: 8 mg daily.
Rectal
Nausea and vomiting associated with cancer chemotherapy
Adult: As suppository: 16 mg given 1-2 hr before treatment.
Hepatic impairment: Moderate or severe hepatic impairment: Max: 8 mg daily.
Rectal
Prevent delayed emesis following chemotherapy
Adult: As suppository: 16 mg once daily, for up to 5 days after the end of a course of chemotherapy.
Hepatic impairment: Moderate or severe hepatic impairment: Max: 8 mg daily.

Reconstitution: Prior to IV infusion, dilute in 50 ml D5W or normal saline.
Incompatibility: Y-site incompatibility: Acyclovir, allopurinol, aminophylline, furosemide, ganciclovir, lorazepam, amphotericin B, amphotericin B cholesteryl sulfate complex, ampicillin, ampicillin/sulbactam, piperacillin, sargramostim, sodium bicarbonate, amsacrine, cefepime, cefoperazone, methylprednisolone sodium succinate.
Contraindications
Use with apomorphine (profound hypotension).
Warnings / Precautions
May cause QT prolongation; caution when used in cardiac diseases, patients who are on medications that can prolong QT or patients with electrolyte abnormalities. Severe hepatic impairment. May mask progressive ileus and/or gastric distension. Pregnancy, lactation.
Adverse Reactions
Headache, malaise/fatigue, constipation; drowsiness, fever, dizziness, anxiety, cold sensation; pruritus, rash; diarrhoea; gynaecological disorder, urinary retention; elevated transaminase; local inj site reaction (pain, redness, burning); paresthesia; hypoxia. Rarely: Anaphylaxis, angina, bronchospasm, ECG changes, extrapyramidal symptoms, grand mal seizure, hypokalaemia, tachycardia, vascular occlusive events.
Overdose Reactions
Sudden transient blindness, severe constipation, hypotension, and vasovagal episode with transient secondary heart block. Treatment is supportive.
Drug Interactions
Rifampicin and other CYP3A4 inducers reduce levels/effects of ondansetron.
Potentially Fatal: Concurrent use may increase the hypotensive effect of apomorphine; avoid concurrent use.
See Below for More ondansetron Drug Interactions
Food Interactions
Extent of absorption increased with food. St John's wort may reduce serum levels of ondansetron.
Mechanism of Actions
Ondansetron antagonises 5-HT3 receptor, blocking serotonin, both peripherally on vagal nerve terminals and centrally in the chemoreceptor trigger zone.
Onset: Approx 30 minutes.
Absorption: Peak plasma concentrations: Oral: 1.5 hr; rectal: 6 hr.
Distribution: Extensively distributed. Protein-binding: 70-75%.
Metabolism: Hepatic via multiple enzymatic pathways.
Excretion: Via urine (44-60% as metabolites, 5-10% as unchanged), faeces (approx 25%). Terminal elimination half-life: Oral/parenteral: 3 hr; rectal: 6 hr; elderly/renal impairment: prolonged, approx 5 hr; severe hepatic impairment: 15-32 hr.
Administration
May be taken with or without food.
Storage Conditions
Oral: Oral solution: Store at 15-30 °C. Protect from light. Tablet: Store at 2-30°C . Parenteral: Vial: Store at 2-30°C. Protect from light. Stable with D5W or normal saline for 48 hr at room temperature.
ATC Classification
A04AA01 - ondansetron ; Belongs to the class of serotonin (5HT3) antagonists. Used for the prevention of nausea and vomiting.
Storage
Oral: Oral solution: Store at 15-30 °C. Protect from light. Tablet: Store at 2-30°C . Parenteral: Vial: Store at 2-30°C. Protect from light. Stable with D5W or normal saline for 48 hr at room temperature.
Available As
  • Ondansetron 1 mg
  • Ondansetron 2 mg
  • Ondansetron 30 mg
  • Ondansetron 4 mg
  • Ondansetron 50 mg
  • Ondansetron 8 mg
  • Subscribe for latest updates

    Subscribe to our e-mail newsletter to receive updates.

    No comments yet.

    Post Review about Ondansetron


    Ondansetron Containing Brands

    We are Developing Our database, More results coming soon.

    Ondansetron is used in following diseases

    We are Developing Our database, More results coming soon.

    Drug - Drug Interactions of Ondansetron

    We are Developing Our database, More results coming soon.