Increased effect of multiple doses of 40 749 RP a new long acting gastric antisecretory agent.

40,749 RP, a pyridyl-2-tetrahydrothiophene derivative is known to be a potent gastric antisecretory agent in animals and man. In 27 healthy volunteers in four double-blind cross-over studies, this activity has been examined against basal and pentagastrin stimulated gastric acid secretion. The effect of a single oral dose of 2 mg/kg was still present after 12, 24 and 48 h. The effect of 1 mg/kg was definitely increased after treatment for 7 days as compared to a single dose of 1 mg/kg.