This is a highly selective 5-HT3 receptor antagonist.

Indications: management of nausea and vomiting induced by cytotoxic chemotherapy and radiotherapy; Prophylaxis and treatment of post-operative nausea & vomiting.

Cautions: pregnancy; breast-feeding; moderate or severe hepatic impairment.

Contra-indications: hypersensitivity reactions.

Side Effects: constipation; headache; flushing and warmth in the head and epigastrium.

Dose: dose is flexible in the range of 8-32 mg a day. Adult, moderately emetogenic chemotherapy or radiotherapy, 8 mg by slow injection immediately before treatment or orally 1-2 hours before treatment followed by 8 mg orally twelve-hourly. To protect against delayed emesis after the first 24 hours, treatment should be continued orally, 8 mg twice daily for up to 5 days after a course of treatment.

Highly emetogenic chemotherapy, a single dose of 8 mg by slow injection immediately before chemotherapy, followed by 2 further IV doses of 8 mg 2-4 hours apart or by a constant IV infusion of 1 mg/hour for up to 24 hours. In highly emetogenic chemotherapy, the efficacy may be enhanced by the addition of a single IV dose of dexamethasone 20 mg given before chemotherapy.

Child, single IV dose of 5 mg/m immediately before chemotherapy, then 4 mg orally twice daily for 5 days. Prevention of postoperative nausea & vomiting: 16 mg 1 hr. before or 8 mg1 hr. before anesthesia followed by 8 mg at intervals of 8 hrs. for further 2 doses. Alternately, IM or slow IV injection, 4 mg at induction of anesthesia Treatment of postoperative nausea & vomiting: IM or slow IV injection, 4 mg.