Inhibitor of H+-K+-ATP, the dextrorotatory isomer of omeprazole. Reduces the secretion of hydrochloric acid in the stomach by specific inhibition of the proton pump in parietal cells. The therapeutic use includes gastroesophageal reflux disease: erosive reflux esophagitis (treatment), prevention of relapse in patients with healed esophagitis, symptomatic treatment of GERD.