Famotidine: an appraisal of its mode of action and safety.

Famotidine is a potent histamine (H2)-receptor antagonist that binds to the H2 receptor in a competitive reversible manner as shown by in vivo, in vitro, and clinical studies. Famotidine has shown no evidence of carcinogenicity, mutagenicity, or teratogenicity in extensive and adequately designed safety assessment studies. The drug produces neither prolonged anacidity nor doses its use result in significant elevations of serum gastrin levels beyond those seen with other available H2-receptor antagonists when used as recommended for the treatment of ulcer disease. Taken together, these data demonstrate no undue or disproportionate risk to the use of famotidine.