Which of the following is a 'Protein Pump Inhibitor'?: (A) Ranitidine, (B) Misoprostol, (C) Omeprazole, (D) Laxatidine
Answer is C. Omeprazole is a proton pump inhibitor, it inhibits gastric acid secretion. It inhibits the H+ K+ ATPase enzyme in the apical membrane of parietal cells, thereby reducing acid secretion. Acid secretion resumes only when new H+ K+ ATPase is formed. It is the treatment of choice for peptic ulcer, gastroesophageal reflux disease, and Zollinger Ellison syndrome. Ref: Essentials of Medical Pharmacology By KD Tripathi, 5th Edition, Page 589 - 94.