If the patient does not have any discomfort, such as abdominal pain, diarrhea, bloating, bleeding stools, mucus stools and black stools, it is usually possible to do it once in 3-5 years, and it is not necessary to do it regularly, because colonoscopy is after all a traumatic examination, which will open the intestine through gas, and it will have certain damage to the intestinal mucosa, intestinal flora and peristalsis. and intestinal peristalsis can be damaged. If a patient has abdominal pain or even black blood or mucus stools, he or she needs to be examined as early as possible because lesions may appear within six months. For patients who have undergone colonoscopy, it is mainly based on the symptoms to determine when to go back for re-examination. Usually pay attention to a light diet and avoid foods that are too spicy and stimulating, high in salt and fried.