cimetidine brands

Molecular formula: C10H16N6S

Cimetidine binds to an H₂-receptor located on the basolateral membrane of the gastric parietal cell, blocking histamine effects. This competitive inhibition results in reduced gastric acid secretion and a reduction in gastric volume and acidity. H2 antagonists inhibit gastric acid secretion elicited by histamine & other H2 agonists in a dose-dependent, competitive manner; the degree of inhibition parallels the concentration of the drug in plasma over a wide range. The H2 antagonists also inhibit acid secretion elicited by gastrin &, to a lesser extent, by muscarinic agonists. Importantly, these drugs inhibit basal (fasting) & nocturnal acid secretion & that stimulated by food, sham feeding, fundic distention, & various pharmacological agents; this property reflects the vital role of histamine in mediating the effects of diverse stimuli. The H2 antagonists reduce both the volume of gastric juice secreted & its H+ concentration. The output of pepsin, which is secreted by the chief cells of gastric glands (mainly under cholinergic control), generally falls in parallel with the reduction in volume of gastric juice. /H2 antagonists/ Cimetidine blocks H2-receptors, which in part are responsible for the inflammatory response, in the cutaneous blood vessels of humans. The effects of cimetidine, omeprazole and atropine sulfate on the healing of acetic acid-induced gastric ulcers in rats with limited food intake time (9:00-10:00 am and 5:00-6:00 pm) were evaluated 15 days after the acid injection. Oral repeated admin of cimetidine (25-100 mg/kg twice daily) or omeprazole (10-50 mg/kg once daily) dose dependently accelerated ulcer healing. ... A single oral admin of omeprazole (50 mg/kg) or cimetidine (100 mg/kg) resulted in potent and long-lasting anti-acid secretory and gastrin-releasing actions. The degree and duration of anti-acid secretion by atropine sulfate were equal to those of cimetidine, but the elevation of gastrin release by atropine sulfate was weak and temporary. These results indicate that the gastric ulcers of rats with a limited food intake time are useful for evaluating the healing effects of cimetidine and omeprazole on gastric ulcers. In addition, the effects of both drugs may be related to the incr gastrin release rather than to the reduced acid secretion. Both KB-5492, a new anti-ulcer agent, and cimetidine, admin po at 25-200 mg/kg, dose-dependently prevented cysteamine (400 mg/kg, sc)-induced duodenal ulcers in rats with ED50 values of 63 and 40 mg/kg, respectively. Anti-ulcer doses of cimetidine, but not KB-5492, inhibited gastric acid hypersecretion induced by cysteamine (400 mg/kg, sc). In contrast, anti-ulcer doses of KB-5492, but not cimetidine, incr duodenal HC03- secretion in normal anesthetized rats. These findings suggest that KB-5492 prevents cysteamine-induced duodenal ulcers by stimulating duodenal HC03- secretion, whereas cimetidine does so by inhibiting cysteamine-induced gastric acid hypersecretion.

Source: PubChem (NCBI) · compound 2756