The anal fistula change without anesthesia is considered to be associated with a variety of factors such as less severe symptoms, tolerance, etc. The specifics need to be known under the judgment of the doctor, not subjective. 1. less severe symptoms: may be due to the symptoms of anal fistula is not so serious, generally in the change of medicine in the pain is not enough to reach the standard of anesthesia, therefore, anal fistula change is generally not anesthesia. 2. strong tolerance: under normal circumstances, anal fistula medicine change is painful, but the degree of pain depends mainly on the size of the anal fistula wound, the depth of the lesion and other factors to decide, if the trauma is not very large, the pain is generally tolerable. Anal fistula medicine change should pay attention to the wound clean and tidy, so as not to cause bacterial infection, if there are other fever and other symptoms of discomfort, should promptly inform the doctor.