Clinically there is no such thing as an easy colonoscopy, but the patient should follow the doctor’s instructions and there are certain contraindications. Enteroscopy in the clinic is mainly applicable to intestinal masses and intestinal inflammatory diseases, but for the elderly and frail as well as the cardiovascular base of the population is poor, it is not appropriate to carry out the examination, in the process of the examination, may lead to hemodynamic changes, but also induced cerebral hemorrhage, cerebral infarction, angina pectoris, myocardial infarction and other complications. At the same time, some patients are unable to tolerate the introduction of diarrhea before colonoscopy, such as intestinal infarction, if a large number of laxatives are taken, it will lead to aggravation of the condition, and even intestinal perforation. Therefore, patients are not allowed to do it without authorization and need to do it strictly under the guidance of doctors. And patients will also be in the early stage of the examination due to the air gathered in the large intestine, abdominal distension and other uncomfortable symptoms, but most patients will gradually disappear after a few hours, if the symptoms are obvious, but also need to inform the doctor in time to take appropriate measures. Patients are advised to choose whether or not to undergo colonoscopy according to their own situation and pay attention to the relevant matters before and after the examination after the doctor’s assessment.