Excessive secretion of fluids in the anus, or poor anal closure, resulting in these fluids sneak out of the anus, stimulating the skin, thus causing itching, dampness and other symptoms. Common intra-anal diseases such as proctitis, sinusitis, etc., due to the anatomical location from the anal opening closer, local inflammation will cause increased exudation in the intestinal lumen, and our anus on the formation of the stool strong fixed uptake of the liquid occlusion ability is poor, these fluids in the intestinal lumen, because of the intestinal wall can adapt to this environment, there will be no obvious discomfort. But overflow to the anus outside, our skin can not tolerate, so the patient will feel the skin around the anal opening and wet and itchy. In addition, there is a class of intra-anal diseases can lead to poor anal closure, intestinal fluid is more likely to seep out, inducing anal itching, such as common hemorrhoids and so on. Our understanding of hemorrhoids, often limited to hemorrhoids caused by bleeding and swelling out, in fact, everyone has “hemorrhoids” in the anus, the normal state of anal closure to assist the role. But to really help the anus to close, must be the right size, each in its place. Just as our teeth, if uneven, will cause oral closure is not strict, bad life and defecation habits, will make the hemorrhoids congested and enlarged or out of the normal position, then the closure of the anus will be affected, the intestinal fluid can not be retained in the anus, “out of the chaos”, secondary to anal itching. Therefore, for the symptoms of itchy skin outside the anus, it is necessary to carry out the corresponding examination of intra-anal diseases. If there is an internal cause, then only “from the inside and outside” treatment, in order to achieve real results.