Timeline Shows PPI Approval, Complications, And Lawsuits Proton pump inhibitor (PPI) medications like Prilosec® (omeprazole), Prevacid® (lansoprazole), and Nexium® (esomeprazole) block the gastric proton pump enzyme in the stomach lining, reducing the production of gastric acid that causes heartburn and other peptic-acid disorders. The U.S. Food and Drug Administration (FDA) approved the first PPI—Prilosec—in 1989. In the […]