There is no clear regulation on how long the colonoscopy can be done for the second time, generally in a week or so can be done for the second time, the specific need to be decided by the doctor according to the patient’s condition. Colonoscopy generally refers to the electronic colonoscopy, when doing colonoscopy, will cause some stimulation to the anus and intestines, and the current colonoscopy is mostly painless colonoscopy, the need for injection of anesthetics, if the time is too short may cause some harm to the body, generally need an interval of about a week to do the second time. In addition, after the colonoscopy, you should try to avoid eating spicy and irritating food. Fasting for three days is also usually required if biopsy or polypectomy is taken through colonoscopy. If there is persistent abdominal pain after the colonoscopy, or if there is blood in the stool in large quantities, you should also inform your physician promptly.