Colonoscopy is not recommended during the acute stage of diarrhea, but can be done when the condition is in remission or stable. Colonoscopy is a kind of slender and bendable medical examination instrument, which can enter the rectum, colon and other intestinal tract through the anus, and present the image on the display screen, so that the examining doctor can visualize the internal situation of the colon and the large intestine, and can assist in the diagnosis of unexplained lower gastrointestinal bleeding, chronic diarrhea, and abdominal mass and other diseases. However, when the patient is in the acute stage of diarrhea, it is not recommended to perform colonoscopy, at this time the intestinal mucosa may be congestion, edema and other serious conditions, colonoscopy may cause irritation to the intestinal mucosa, causing perforation and other conditions, in the diarrhea after the relief or stable period of the feasibility of colonoscopy to clarify the cause of diarrhea. Patients with diarrhea, it is recommended to go to the hospital in a timely manner, after the condition improves, improve the relevant examination to clarify the causes of diarrhea, targeted treatment.