Each mL injection solution contains Tropisetron hydrochloride 1.13 mg equivalent to Tropisetron 1 mg.
Pharmacology: Pharmacokinetics: Tropisetron is well absorbed after oral doses. Peak plasma concentrations are achieved within 3 hours. Absolute bioavailability depends on the dose since first-pass metabolism is saturable. It is 71% bound to plasma proteins. Tropisetron is metabolised by hydroxylation and conjugation, and metabolites are excreted mainly in the urine with a small amount in the faeces. The cytochrome P450 isoenzyme CYP2D6 is involved in tropisetron metabolism, and shows genetic polymorphism. The eliminations half-life is about 8 hours in extensive metabolisers and up to 45 hours in poor metabolisers. Clearance is also reduced in patients with renal impairment.
Tropisetron is a 5-HT3 antagonist with an antiemetic action. It is used in the prevention of nausea and vomiting induced by cytotoxic therapy in the treatment and prevention of postoperative nausea and vomiting.
Tropisetron is given as the hydrochloride by slow intravenous injection or infusion. For the prophylaxis of acute nausea and vomiting associated with cytotoxic chemotherapy, a single dose of 5 mg may be given by slow intravenous injection or infusion on the day of treatment, shortly before chemotherapy. The injection is given over not less than 1 minute; it may be given into a running infusion. For infusion, it is diluted into 100 mL of a suitable infusion fluid (such as sodium chloride 0.9% or glucose 5%), and given over 15 minutes. Subsequent doses of 5 mg daily are given orally, in the morning at least one hour before food, for a further 5 days.
Children over 2 years of age may be given 200 micrograms/kg (maximum dose 5 mg) before chemotherapy, by intravenous injection over at least 1 minute, or by infusion (at a concentration of 50 micrograms/mL in a suitable infusion fluid). In children weighing less than 25 kg the same dose may be given intravenously once daily for up to a further 4 days as required. In those weighing more than 25 kg, a dose of 5 mg may be given orally once daily for up to a further 5 days; if oral dosage is not possible the same dose may be given intravenously. For the treatment of postoperative nausea and vomiting in adults, 2 mg may be given by slow intravenous injection (over not less than 30 seconds), or by infusion (over 15 minutes), within 2 hours of the end of anaesthesia. For prophylaxis, the same dose may be given shortly before induction of anaesthesia.
The drug should therefore be used with caution in patients with cardiac rhythm or conduction disturbances. Care should be taken when driving or operating machinery. No dosage reduction is considered necessary in renal or hepatic impairment despite possible reductions in clearance.
Fatigue, abdominal pain, and diarrhoea may occur. Visual hallucinations, and an increase in blood pressure in patients with preexisting hypertension, have been noted at high repeated doses. ECG changes such as prolongation of QT interval have been noted with high-dose intravenous tropisetron.
Drugs that induce or inhibit hepatic enzymes may affect plasma concentrations of tropisetron. Licensed product information considered that any changes are usually unlikely to be clinically relevant with the recommended doses. Tropisetron should be used with caution with antiarrhythmics, beta blockers, or drugs likely to prolong the QT interval, including those likely to cause electrolyte disturbances.
Store at temperatures not exceeding 30°C.
A04AA03 - tropisetron ; Belongs to the class of serotonin (5HT3) antagonists. Used for the prevention of nausea and vomiting.
Inj (amp) 5 mg/5 mL x 5 mL x 10's.