Lansoprazole is a new drug that can inhibit gastric acid secretion. It can significantly inhibit the basic gastric acid secretion and the gastric acid secretion induced by all stimulants (such as histamine, carbachol, etc.), and its acid inhibition effect is better than that of H2 receptor blocker. The inhibition degree is obviously dependent on the concentration. Lansoprazole can rapidly transform into sulfosulfonic acid and sulfosulfonic acid derivatives through parietal cell membrane under acidic conditions, and has inhibitory effect on Helicobacter pylori (HP), which is 4 times as much as omeprazole. It is clinically used for duodenal ulcer, gastric ulcer, anastomotic ulcer, reflux esophagitis, zolinger Ellison syndrome; The curative effect of gastrinoma is remarkable. When taking lansoprazole, we must pay attention to the dosage. Overdose of lansoprazole will cause mild headache, dizziness, drowsiness, diarrhea, rash and itching; Anorexia, fatigue and proteinuria were rare; Impotence, anxiety, depression and myalgia were occasionally seen; The levels of transaminase, total cholesterol, leucopenia, thrombocytopenia and eosinophilia were increased. These adverse reactions, not only did not play a therapeutic effect, but may aggravate the disease, and cause some unknown chain reaction.