Lansoprazole is a proton pump inhibitor that specifically inhibits the sodium-potassium ATPase of the gastric mucosal wall cells, commonly known as the proton pump, thereby blocking the final step of gastric acid secretion, inhibiting basal gastric acid secretion in a dose-dependent manner, and also inhibiting gastric acid secretion in a stimulated state. Lansoprazole can be used clinically for gastric ulcer, duodenal ulcer, reflux esophagitis, and lansoprazole can also be used for peptic bleeding and can play a role in preventing acute stress ulcers. In short, the main function of lansoprazole is to inhibit gastric acid, which can improve the related diseases caused by excessive gastric acid.