The main reasons for anal distension and wanting to have a bowel movement include intestinal dysfunction, perianal neurosis, inflammatory stimulation, localized anorectal lesions, hemorrhoids, etc. No abnormality in colonoscopy can exclude anorectal lesions. 1. Intestinal dysfunction: when intestinal dysfunction occurs, stools may be stored in the rectum for a long time and cannot be discharged, causing anal swelling, which can be improved by regular diet, avoiding exertion, anxiety and so on. 2. Perianal neurosis: mostly due to mental tension, depression, anxiety and other reasons, manifested as anal swelling, perianal radiating pain, frequent bowel movements, can be psychological counseling, if necessary, the use of anti-anxiety or depression and other drugs. 3. Inflammatory stimulation: gynecological diseases such as pelvic inflammatory disease, cervicitis and other inflammatory stimulation of the intestinal tract can lead to anal distension and always have the urge to go, you can take metronidazole and other drugs. Prostatitis can also lead to the surrounding pelvic floor tissue congestion and rectal pressure, stimulation of excitation of the pelvic floor defecation nerves produce anal distension, you can take drugs such as prostate Schuler. 4. hemorrhoids: internal hemorrhoids more serious rectal mucosa out of the anus is stuck anal distension, can be injected sclerotherapy, rubber ring ligation therapy or surgical treatment. Patients with the symptoms of anal distension, it is recommended to go to the regular hospital, complete anoscopy, pelvic CT and other tests to clarify the cause of the disease, under the guidance of the doctor standardized treatment.