There is now experimental evidence that long-term use of omeprazole can cause cancer. Omeprazole is suitable for the treatment of duodenal ulcer, gastric ulcer, stress ulcer, reflux esophagitis and Zuo – Ai syndrome, after the use of headache, nausea, diarrhea, increased serum aminotransferase, dizziness, drowsiness, insomnia, skin rash and other adverse reactions, usually disappear automatically. Nursing women, liver and kidney insufficiency should be used with caution, allergic to the product, pregnant women, severe renal insufficiency and infants and children are prohibited. Carcinoid tumors may occur with long-term use. Patients who want to use omeprazole are advised to go to regular hospitals, consult professional doctors, cooperate with doctors to complete relevant examinations, and avoid blind use of drugs.