Cimetidine: effect on pancreatic and biliary function in man.

1 Pancreatic and biliary function were studied in eight patients taking oral cimetidine (1.6 g/day for 6 weeks) for endoscopically confirmed active peptic ulcer disease. 2 Postprandial jejunal tryptic activity and bile acid concentration were unchanged during cimetidine given for 1 and 6 weeks. 3 Postprandial gallbladder emptying was also unchanged. 4 Direct examination of postprandial upper jejunal aspirate for deconjugated bile acids was negative in all patients; but the more sensitive [14C]-glycocholate bile acid breath test showed a significant increase in breath 14CO2, indicating increased bacterial deconjugation of bile acids in the gastrointestinal tract.