Taking laxatives before having a colonoscopy and pulling mucus after taking the medication may be a normal phenomenon caused by increased intestinal secretions stimulated by the medication, or it may be caused by other diseases such as enteritis. Colonoscopy is usually used to assist in the diagnosis of enteritis, bowel cancer, intestinal polyps and other diseases. Laxatives such as polyethylene glycol are usually drunk before the colonoscopy to speed up gastrointestinal peristalsis, promote excretion, and prepare for intestinal cleansing in order to improve the accuracy of the diagnosis. If there is no lesion in the intestinal tract, after drinking laxatives, due to the stimulation of drugs, the intestinal mucosa will secrete a small amount of mucus, so the discharge of mucus is a normal phenomenon, and can be relieved after a few days of rest. If a large amount of mucus is discharged, it may also be due to enteritis, ulcerative colitis and other diseases, due to inflammation stimulation leading to increased intestinal mucosal secretions, drink laxatives to promote mucus discharge. Doing colonoscopy after pulling mucus, after discharging the changes caused by laxatives, should be timely under the guidance of the doctor to clarify the cause of the disease, timely treatment, so as not to delay the condition.