Tummy ache after colonoscopy usually relieves gradually after 1-2 days and disappears within 1 week at most. Tummy ache after colonoscopy is relatively common and can be caused by many reasons. Firstly, the laxatives used during the preparation of the intestine can cause certain stimulation to the intestinal wall, which can lead to spasm of the intestine after colonoscopy and cause stomach pain; secondly, the stimulation and damage to the intestine during the colonoscopy due to catheter stimulation, drug stimulation and pathological biopsy can also lead to stomach pain after colonoscopy. Therefore, patients should fast for 1-2 hours after colonoscopy and start to eat mainly liquid food and low residue diet, without spicy food and alcohol, so as not to stimulate the intestinal wall and aggravate the abdominal pain; they can also use some intestinal mucosal protective agents or drugs that promote the recovery of intestinal mucosa, such as montelukast and rehabilitation new liquid to promote the recovery of intestinal mucosa. If the abdominal pain does not decrease or exceeds 1 week, you should go to the hospital promptly.