Ranitidine is commonly used for the treatment of Gastro-Oesophageal Reflux Disorder (GERD). It is Manufactured and sold in Brands like Aciloc, Zinetac,Rantac OD.
Ranitidine is a specific rapidly acting histamine H2 receptor-antagonist. It inhibits basal and stimulated secretion of gastric acid, reducing both the volume of the acid and pepsin content of the secretion.
Ranitidine indicated for treatment of Gastro-Oesophageal Reflux Disorder (GERD).
Dose and Method of Administration
To be taken once daily or as directed by the physician.
Hypersensitivity to the active substance or any of the excipient. It should be carefully used in pregnancy and lactation, Pediatric and Geriatric Population.
Warning and Precautions
Malignancy : The possibility of malignancy should be excluded before the commencement of therapy in patients with gastric ulcer and in patients of middle age and over with new or recently changed dyspeptic symptoms) as treatment with ranitidine may mask symptoms of gastric carcinoma.
Renal Disease : Ranitidine is excreted via the kidney and so plasma levels of the drug are increased in patients with renal impairment. The dose should be adjusted for Patients with renal impairment. Regular supervision of patients who are taking non-steroidal anti-inflammatory drugs concomitantly with ranitidine is recommended, especially in the elderly. Current evidence shows that ranitidine protects against NSAID associated ulceration in the duodenum and not in the stomach.
Rare clinical reports suggest that ranitidine may precipitate acute porphyric attacks. Ranitidine should therefore be avoided in patients with a history of acute porphyria.
In patients such as the elderly, persons with chronic lung disease, diabetes or the immunocompromised, there may be an increased risk of developing community-acquired pneumonia. A large reported epidemiological study showed an increased risk of developing community-acquired pneumonia in current users of ranitidine alone versus those who had stopped treatment, with an observed adjusted relative risk increase of 1.82 (95% CI 1.26-2.64). Post-marketing data indicate reversible mental confusion, depression, and hallucinations have been reported most frequently in severely ill and elderly patients.
Ranitidine has the potential to affect the absorption, metabolism or renal excretion of other drugs. The altered pharmacokinetics may necessitate dosage adjustment of the affected drug or discontinuation of treatment Interactions occur by several mechanisms including:
1) Inhibition of cytochrome P450-linked mixed-function oxygenase system: Ranitidine at usual therapeutic doses does not potentiate the actions of drugs which are inactivated by this enzyme system such as diazepam, lidocaine, phenytoin, propranolol and theophylline. There have been reports of altered prothrombin time with coumarin anticoagulants (e.g. warfarin). Due to the narrow therapeutic index, close monitoring of increased or decreased prothrombin time is recommended during concurrent treatment with ranitidine.
2) Competition for renal tubular secretion: Since ranitidine is partially eliminated by the cationic system, it may affect the clearance of other drugs eliminated by this route. High doses of ranitidine may reduce the excretion of procainamide and N-acetyl procainamide resulting in increased plasma level of these drugs.
3) Alteration of gastric pH:
The bioavailability of certain drugs may be affected. This can result in either an increase in absorption (e.g. triazolam, midazolam, glipizide) or a decrease in absorption (e.g. ketoconazole, atazanavir, delavirdine, gefitinib). There is no evidence of an interaction between ranitidine and amoxicillin or metronidazole. If high doses (2 g) of sucralfate are co-administered with ranitidine the absorption of the latter may be reduced. This effect is not seen if sucralfate is taken after an interval of 2 hours.