Ranitidine has the effect of inhibiting gastric acid, mainly applicable to gastroduodenal ulcer, reflux esophagitis and other diseases. Ranitidine belongs to the H2 receptor blocker, can competitively block the histamine and H2 receptor binding effect, has a strong inhibition of gastric acid effect, for duodenal ulcer, gastric ulcer, reflux esophagitis, Ai Zhuo syndrome and other gastric acid hypersecretory diseases with therapeutic effect. Ranitidine may cause nausea, vomiting, constipation, fatigue, rash, dizziness and other adverse reactions, during the period of taking attention to liver and renal insufficiency should be used with caution, long-term use of vitamin B12 deficiency may lead to vitamin B12 deficiency, for suspected cancerous ulcers it is recommended to clarify the diagnosis to avoid delay in treatment. It is recommended to take Ranitidine under the guidance of a professional doctor, and not to use the drug without authorization.