Pharmacological evaluation of cimetidine, a new histamine H2-receptor antagonist, in healthy man.

Cimetidine, a new H2-receptor antagonist, was safely administered to eighteen healthy man by the intravenous, intraduodenal or oral route. 2 When gastric secretion was maximally stimulated by either histamine or pentagastrin, the simultaneous administration of cimetidine produced marked inhibition of both acid and pepsin secretion. 3 Cimetidine was well absorbed by mouth and had a blood half-life of 2 hours.