The correct way to drink mannitol bowel cleansing is to mix mannitol and water in a certain proportion and drink it in portions. Mannitol is hypertonic liquid, into the intestinal lumen is not absorbed by the intestinal tract, but also can reduce the intestinal absorption of water, stimulate peristalsis of the intestinal lumen, accelerate the discharge of stools, so as to achieve the purpose of softening the bowel cleansing. Two days before the purging should pay attention to the food eaten as little slag as possible, twelve hours before the purging to fast, will be 20% of mannitol 500 ml, in accordance with the ratio of 1:3 to 2000 ml of water, within two hours to drink, to promote gastrointestinal movement, until the discharge of water-like stools to complete the purging. The use of mannitol cleansing method must be used scientifically under the guidance of a doctor, can not be used on their own, so as not to affect the effect of cleansing, jeopardizing health.