You can drink water anytime after drinking lactulose, and patients are advised to drink more water as appropriate. Lactulose is a western drug name, the main ingredient is lactulose, its oral liquid dosage form is colorless to light brownish yellow clear viscous liquid, slightly milky light, as a laxative, has the effect of laxative, for the treatment of chronic constipation, habitual constipation; but also for the treatment, prevention of hepatic coma or pre-comatose state. Adverse effects of lactulose are possible bloating for the first few days; abdominal pain and diarrhea may occur when large amounts are taken; electrolyte disorders due to diarrhea may occur if large doses are taken over a long period of time. Galactosemia and its hypersensitivity are contraindicated. If you need to use the drug, please write a prescription under the supervision of a physician and take it according to the doctor’s instructions. Do not take it by yourself to avoid affecting your health.