Control of Gastric Acid Secretion by Histamine H2-Receptor Antagonists; A Pharmacological Dream Come True?*

Summary: A pharmacological break-through has resulted in the development of an effective inhibitor of histamine stimulated gastric acid secretion. The development of histamine H2-receptor antagonists which inhibit also vagal and pentagastrin stimulated acid secretion support the hypothesis that histamine is the final common mediator of gastric acid secretion. Metiamide, an orally effective inhibitor of acid secretion in man and animal is now ready for carefully controlled clinical trials in the treatment of peptic ulcer. While this drug has no anticholinergic side effects it has shown some toxicity in animals studies, a proportion of which is due to its thiourea side chain. Already, one patient treated with metiamide has developed agranulocytosis which reponded to stopping the drug. In spite of this set-back the outlook for medical control of gastric acid secretion and possibility of peptic ulcer disease has distinctly brightened.