Histamine H2-antagonists--past, present and future.

In this selective review of histamine H2-antagonists, we emphasize the significance of burimamide, the first specific H2-antagonist, in physiology and pharmacology and describe how its discovery led to the development of cimetidine as a new treatment of acid-aggravated disease of the alimentary tract. Developments since cimetidine, include ranitidine, which is a more potent, selectively acting H2-antagonist. A new series of H2-blockers with prolonged activity is discussed, and exemplified, particularly AH 23844. Its prolonged action and its unusual, apparently insurmountable, blocking action is explained in fundamental physicochemical terms.