Drainage of perianal abscess is usually about 3~7 days, may drain clean, such as pus cavity is deep and large, it may take a little longer. Perianal abscess is an acute purulent infection around the anorectal canal and rectum, purulent secretions accumulate to form an abscess, most need to be incised and drained, the beginning of the drainage flow is more, the color is more yellow, the small abscess will drain clean in about 3 days, the larger abscess will drain clean in about 7 days or maybe a little longer. To determine whether the drainage is clean, you can observe the amount and color of the drainage fluid, when the amount of drainage fluid decreases, less than 20 ml or there is no new pus flow for a period of time, and the color becomes lighter usually means that it has been drained cleanly. When the patient occurs perianal abscess, there will be pain, swelling and other discomforts, should be timely to the hospital for examination, need to drain the timely incision and drainage, and must drain clean, in order to reduce the chances of not recurring, will not make the local and systemic symptoms of infection aggravation.