There are many kinds of enteroscopy laxatives, such as mannitol, polyethylene glycol and salts, etc. At present, the main clinical choice is polyethylene glycol, which is relatively safe. 1. Polyethylene glycol: after taking it, it will not interfere with the internal environment of the human body, will not affect the accuracy of the results of colonoscopy, will not produce adverse reactions to the human body, and the colonoscope can clearly show the whole intestinal tract when it passes through the intestinal tract. Compound Polyethylene Glycol Electrolyte is mainly composed of Polyethylene Glycol Anhydrous Sodium Sulfate, Sodium Chloride, Potassium Chloride, and Sodium Bicarbonate, which can replenish the electrolytes lost by the human body, and help to prevent water and electrolyte disorders. 2. Salts: such as magnesium sulfate or sodium phosphate salts, which intervene in the body’s internal environment. When magnesium sulfate is used very few patients develop electrolyte disorders and hypermagnesemia. 3. Mannitol: the main component of mannitol is large molecule sugar, through fermentation will produce some gas, if the patient is ready to polyp electrolysis through colonoscopy, the use of mannitol has the risk of explosion. Doing colonoscopy is recommended to go to a regular hospital. Before doing colonoscopy, start a liquid diet the day before and fast after 8:00 pm.