The numbness of the anal opening may be related to hemorrhoids, anal eczema, anal fistula and other causes, it is recommended to consult a doctor in time to clarify. 1. Hemorrhoids: anorectal diseases caused by improper diet, poor bowel habits, sedentary and other reasons, can be manifested as anal itching, blood, constipation and other symptoms. The numbness of the anal opening may be caused by the itching caused by hemorrhoids. 2. anal eczema: mostly caused by anal diseases, poor local hygiene, endocrine disorders, clinical pain, itching, perianal skin ulceration and other symptoms, numbness of the anal opening may be anal eczema caused by pain, itching and other symptoms of performance. 3. anal fistula: occurs in the anorectal periphery of the abscess ulcerated or incision drainage of the sequelae of the lesion, generally and bacterial infection, perianal abscess, rectal anus injury and other reasons related to the anus can be manifested as anal swelling and pain, pus, itching and other symptoms. The numbness of the anal opening can also be considered as the manifestation of anal fistula caused by anal swelling and pain, pus and other symptoms. If there is any of the above factors, you should go to the hospital for examination, clarify the cause of the disease and give appropriate treatment.