Before colonoscopy, you can take polyethylene glycol electrolyte bulk, lactulose, and mannitol to prepare for bowel cleansing. Enteroscopy, generally referred to as colonoscopy, is to make the enteroscopic probe enter through the anus and observe whether the mucosa of the rectum, sigmoid colon, descending colon, transverse colon, ascending colon and cecum is congested, edematous, erosive and with or without redundancy, etc., so as to carry out the judgment of the disease. Treatment such as stopping bleeding and removing polyps under colonoscopy can also be performed. Before doing colonoscopy need to take polyethylene glycol electrolyte bulk, this is a kind of osmotic laxative, after taking so that the osmotic pressure in the intestinal tract, thus making the intestinal lumen of water and sodium retention, increase the volume of feces, stimulate intestinal peristalsis, and play the effect of cleaning the intestinal tract before colonoscopy, so as to facilitate colonoscopy to be able to observe the intestinal mucosa more clearly, so as to avoid feces and other intestinal contents to affect the examination field of view, thus resulting in misdiagnosis and other situations. Lactulose, mannitol, etc. can also be taken before colonoscopy for intestinal preparation. It should be noted that the drugs need to be taken under the guidance of a doctor and should not be used without authorization.