Effect of preoperative cimetidine and ranitidine on gastric secretion.

To decrease gastric volume and acidity prior to anesthesia and surgery and decrease the risk of aspiration, a prospective double-blind trial comparing two H2 receptor blockers, cimetidine and ranitidine, was performed. Analysis of gastric contents revealed both drugs to be extremely effective in raising gastric pH to the 6-7 range. However, ranitidine was shown to be more effective in decreasing gastric volume.