The effect of ranitidine hydrochloride, a new histamine H2-receptor antagonist, on intrinsic factor secretion.

The effect on intrinsic factor (IF) secretion of eight weeks' continuous treatment with a clinically relevant oral dose of ranitidine hydrochloride, a new histamine H2-receptor antagonist, has been studied in 11 patients with duodenal ulcer. There was no significant difference between the mean IF output during treatment of after drug withdrawal as compared with the control value, despite highly significant (p less than 0.001) reduction in acid output during treatment. In the short term this potent drug is unlikely to cause pernicious anemia from interference with IF secretion, although further study is necessary to exclude this possibility after long-term use.