Kinetics and duration of action of ranitidine on gastric secretion and its effect on pancreatic secretion in duodenal ulcer patients

Abstract

Inhibitory effects of ranitidine, a new H2-receptor antagonist, and cimetidine on histamine and pentagastrin-induced gastric secretion have been compared in duodenal ulcer patients. Compared with cimetidine, ranitidine was found to be about 6-8 times a more potent inhibitor of gastric acid secretion, the inhibition of histamine-induced secretion being competitive, whereas that of pentagastrin-induced secretion not competitive. Ranitidine was an effective inhibitor of pentagastrin-induced secretion 8-12 h after administration. When given in a dose inhibiting gastric secretion by over 90%, it did not affect pancreatic secretion induced by secretin and pancreozymin. The availability of ranitidine, a more powerful inhibitor of gastric secretion, provides an opportunity of a treatment alternative to cimetidine, for peptic ulcer and related diseases.