A circle outside the anus is red may be perianal abscess, perianal eczema, hemorrhoids and other factors, the patient should consult a doctor in a timely manner, clear cause for treatment. 1. Perianal abscess: that is, the soft tissues around the anorectal canal and rectum acute suppurative infection, the patient will have a circle outside the anus red, swollen, painful, and in severe cases there will be a generalized fever, mainly through surgical treatment. 2. Perianal eczema: an inflammatory skin disease that occurs around the anus, patients will have a circle of red anus, itching, overflow, pain, etc., can be used externally tacrolimus, pimecrolimus and other drugs for treatment. 3. hemorrhoids: anal canal or rectal veins are congested and enlarged, patients with acute episodes of blood in the stool, perianal red, pain and other symptoms, such people should pay attention to a light diet, warm water sitz baths when necessary, the pain is serious, you can use topical lidocaine gel, hemorrhoidal suppositories and other treatments or surgical excision treatment. It is recommended that patients go to the hospital for timely examination and diagnosis, to clarify the cause of the disease and give treatment. The above medication and treatment should be carried out under the guidance of a professional doctor, and should not be blindly diagnosed and used on their own to avoid causing adverse reactions.