A colonoscopy usually takes about ten minutes to half an hour to do, but it can take longer if endoscopic treatment is needed. Enteroscopy is a 1cm thick instrument that can be bent through the anus into the intestines for examination. If the intestines are in good general condition and the enteroscope travels smoothly, then the process will be faster. If there are many internal lesions in the intestines, such as multiple intestinal polyps, the general endoscopic treatment such as polypectomy will prolong the examination time, in addition, if the combination of underlying diseases such as ulcerative colon, post-surgical intestinal adhesions, etc., the examination time may be prolonged. Before doing the colonoscopy, it is necessary to be evaluated by a professional doctor to consider whether it is possible to do the colonoscopy and the necessity of the examination by synthesizing the condition and the basic physical condition.