Zantac Injection: 2ml ampoules each containing 50mg ranitidine (as hydrochloride) in 2ml aqueous solution for intravenous or intramuscular administration.
- Duodenal Ulcer.
- Benign Gastric Ulcer
- Post-operative Ulcer
- Reflux Oesophagitis.
- Zollinger-Ellison Syndrome.
- Prophylaxis of stress ulceration in seriously ill.
- Prophylaxis of recurrent haemorrhage from peptic ulcer.
- Prophylaxis of Mendelson's syndrome.
DOSAGE AND ADMINISTRATION
Zantac Injection may be given as:
- a slow (over 2 minutes) intravenous injection of 50 mg, diluted to a volume of 20 ml, every 6-8 hours.
- an intermittent intravenous infusion at 25 mg/hour for two hours, repeated at 6-8 hour intervals.
- an intramuscular injection of 50 mg every 6-8 hours.
In the prophylaxis of upper gastrointestinal haemorrhage from stress ulceration in seriously ill patients a priming dose of 50 mg as a slow intravenous injection followed by a continuous intravenous infusion of 0.125 - 0.250 mg/kg/h may be preferred.
In the prophylaxis of haemorrhage from stress ulceration in seriously ill patients or prophylaxis of recurrent haemorrhage in patients bleeding from peptic ulceration parenteral administration may be continued until oral feeding commences. Patients considered to be still at risk may then be treated with Zantac Tablets 150 mg twice daily.
For prophylaxis of Mendelson s syndrome 50 mg by intramuscular or slow intravenous injection 45 to 60 minutes before induction of general anaesthesia.
Use in children has not been evaluated.
Accumulation of ranitidine with resulting elevated plasma concentrations will occur in patients with severe renal impairment (creatinine clearance less than 50 ml/min). It is recommended in such patients that Zantac be administered in doses of 25 mg.
Zantac is contra-indicated in patients known to have hypersensitivity to any component of the preparation.
WARNINGS AND PRECAUTIONS
The possibility of malignancy should be excluded before commencement of therapy in patients with gastric ulcer as treatment with ranitidine may mask symptoms of gastric carcinoma.
Ranitidine is excreted via the kidney and so plasma levels of the drug are increased in patients with severe renal impairment. The dosage should be adjusted as detailed above under Dosage and Administration, in Renal Impairment.
Bradycardia in association with rapid administration of Zantac Injection has been reported rarely, usually in patients with factors predisposing to cardiac rhythm disturbances.
Recommended rates of administration should not be exceeded.
The use of higher than recommended doses of intravenous H2-antagonists has been associated with rises in liver enzymes when treatment has been extended beyond five days. Rare clinical reports suggest that ranitidine may precipitate acute porphyric attacks. Ranitidine should therefore be avoided in patients with a history of acute porphyria.
Pregnancy and Lactation
Ranitidine crosses the placenta and is excreted in human breast milk.
Like other drugs it should only be used during pregnancy and nursing if considered essential.
Effects on Ability to Drive and Use Machines
Ranitidine, at blood levels produced by standard recommended doses, does not inhibit the hepatic cytochrome P450-linked mixed function oxygenase system. Accordingly, ranitidine in the usual therapeutic doses does not potentiate the actions of drugs which are inactivated by this enzyme; these include diazepam, lignocaine, phenytoin, propranolol, theophylline and warfarin.