Famotidine. The ACG Committee on FDA-Related Matters with primary authorship by G. Friedman. American College of Gastroenterology.

Famotidine is a potent H2 receptor antagonist containing a thiazole ring structure, thus differing chemically from cimetidine and ranitidine. Pharmacologically, famotidine is nine times more potent than ranitidine and 32 times more potent than cimetidine. In the Zollinger-Ellison syndrome famotidine is more potent than cimetidine or ranitidine and has a 30% longer duration of action. Randomized double-blind controlled duodenal ulcer studies reveal famotidine effectively heals active ulcers when compared to placebo and that healing rates are comparable to those seen at 8 wk with ranitidine. Famotidine effectively heals gastric ulcers in 8 wk when compared to placebo. The drug also significantly reduced the recurrence rate of duodenal ulcers in a 6-month controlled trial. Famotidine is a potent H2 antagonist which appears to be safe at high doses, does not cause antiandrogen side effects, and does not interfere with hepatic oxidative metabolism. Further clinical experience will define famotidine's place in the therapeutic armamentarium against peptic ulcer disease.