Due to individual differences in the situation, the specific circumstances of specific treatment, usually lactulose treatment of constipation 1 ~ 2 days can stop. Lactulose is a synthetic disaccharide that is not absorbed by the human body, and when taken by patients with constipation, lactulose is easily decomposed into lactic acid or acetic acid under the action of various enzymes after entering the intestinal tract, so that the osmotic pressure within the intestinal lumen of the patient is elevated, and the water enters the intestinal tract through the osmotic effect to play a role in softening the stool, and at the same time stimulate peristalsis of the gastrointestinal tract to promote bowel movements. Constipated patients in taking lactulose 8 to 12 hours after the phenomenon of defecation, but some patients may be more sensitive to lactulose, may be taking 2 to 3 hours after the gradual effect, when the patient to eat lactulose can be smooth defecation 1 to 2 days after the discontinuation of the drug. In the daily diet should pay attention to drink more water, eat more fresh vegetables and fruits rich in dietary fiber, to avoid constipation again. Long-term constipation patients are recommended to go to a professional hospital in time, under the guidance of the doctor for targeted treatment. Please do not take medication on your own to avoid delaying your condition.