The efficacy of lactulose oral (soluble) solution is mainly to promote defecation, improve ammonia metabolism, etc., the specific use of medication as prescribed by the doctor. Lactulose oral solution can stimulate colonic peristalsis, make bowel movement, but also by stimulating the intestinal bacteria to use ammonia for protein synthesis, and then improve ammonia metabolism, clinically mainly used in the treatment of chronic constipation, intestinal preparation, as well as the prevention and treatment of hepatic encephalopathy. The drug should be contraindicated in people who are allergic to the product, diabetics, patients with galactosemia, people suffering from perforation of the digestive tract, uremia, appendicitis, intestinal obstruction, acute inflammatory bowel disease, abdominal pain of unknown origin, as well as people who are using other laxatives. Adverse reactions such as mild abdominal pain and burning sensation may occur after use, and anorexia, nausea, vomiting, abdominal discomfort, flatulence, abdominal pain, diarrhea, electrolyte disorders and other adverse reactions may occur if the drug is used in large doses. The specific use of drugs should be carried out under the guidance of a specialist, not unauthorized use of drugs.