Usually, the human body does not experience pain or even bleeding in the anus during defecation. If there is tearing pain and blood in the anus during defecation, it may be due to pathological factors such as perianal abscess, anal fissure or hemorrhoids. In this case, you should observe whether there is continuous bleeding and whether such conditions still exist in recent times when defecating, and if the pain is severe, it is recommended to go to the hospital for differential diagnosis. 1. perianal abscess: also known as perirectal abscess, is an infection in the rectal anal canal tissue or in the interstices around it. The infection can spread to the loose fatty connective tissue in the perirectal space and form an abscess, which mainly manifests as skin lesions, itching and severe pain in the anal or rectal area, and the pain is mostly persistent, especially when defecating, and can even cause bleeding. The initial treatment of perianal abscess is mostly surgical drainage, and antibiotic drugs such as amoxicillin can also be used. 2. Anal fissure: it is a chronic ulcer formed by the rupture of the whole layer of the skin of the anal canal below the dentate line, mainly manifested as anal pain, which occurs mostly during defecation, and can also cause periodic pain of anal fissure when squatting or sneezing, which can be persistent and severe after defecation and accompanied by bleeding symptoms, and can be relieved by itself after several hours. It can be relieved by itself after a few hours, and can also be accompanied by constipation and anal itching. The painful anal tears can be relieved by local application of drugs such as lidocaine hydrochloride gel and nitroglycerin ointment to promote wound healing, and the intake of dietary fiber and water should be increased to improve the symptoms of constipation. Among them, external hemorrhoids can manifest as bleeding, anal swelling, pain or itching in the anal area, especially more intense pain when defecating. Hemorrhoids are usually treated surgically, and local medications such as compound lidocaine cream can also be used to relieve painful symptoms, as well as antispasmodic medications such as nitroglycerin ointment to improve symptoms such as bleeding, itching, and difficulty in defecating, and hemorrhoid suppositories can also be given for external use, and in severe cases mucosal circumcision is performed to remove them.