Omeprazole: a new drug for the treatment of acid-peptic diseases.

Omeprazole is the first of a new class of gastric antisecretory drugs, proton pump inhibitors. It inhibits the H+,K(+)-adenosinetriphosphatase enzyme of the gastric parietal cell, resulting in potent, long-lasting suppression of basal and stimulated acid secretion. The drug is currently approved for treatment of gastroesophageal reflux disease and Zollinger-Ellison syndrome. In clinical trials, treatment with omeprazole results in rapid healing of duodenal ulcers; it is also effective in treating gastric ulcer disease. It is uniformly well tolerated without significant adverse effects, although animal studies linked profound long-term suppression of gastric acid secretion with the development of gastric carcinoids. Potential future uses include the prophylaxis of ulceration secondary to stress or use of nonsteroidal anti-inflammatory drugs, and the prophylaxis of recurrent peptic ulcer disease.