Anal canal, perianal skin and perineum itch without any original damage to the intractable itching called anal itching, is a common anal disease, with intense itching, long duration, easy to proliferate and other clinical features, which will bring patients a serious ideological and mental burden, the serious will cause neurasthenia, mental depression and so on. Anus itching of Chinese medicine etiology: Chinese medicine that anal itching and wind most closely related, but there are exogenous wind heat, wind dampness and blood deficiency of the wind. External wind, or wind-heat gathering, wind and dampness with heat, evil stagnation in the camp and guard between the skin coupling, knot and not scattered, the itchy rash, and become itchy; blood deficiency wind, skin coupling needs gas and blood nutrients, blood is smooth and moist skin, blood deficiency can not support the skin coupling, wind dryness is itchy skin, it is a “blood deficiency is wind, the wind is poly Itchy” said. Modern medicine believes that anal itching of the hair of the systemic causes and local causes of two aspects. First, systemic causes: 1, endocrine and metabolic diseases: such as diabetes mellitus, hyperthyroidism, gout, women and men menopausal syndrome. 2, liver and kidney disease: obstructive biliary disease, biliary cirrhosis, nephritis caused by renal failure. 3, gastrointestinal diseases: acute and chronic diarrhea, constipation, ulcerative colitis. 4, blood disorders: anemia, erythrocytosis. 5, parasitic diseases: schistosome, hookworm, ascariasis, especially in the case of the anus, the anus, the anus, the anus, the anus, the anus, the anus, the anus. Ascariasis, especially Ascaris lumbricoides. 6, drug factors: certain antibiotics, morphine, cocaine, oral contraceptives, etc. 7, food factors: allergic to certain foods, such as fish, shrimp, eggs and other allergic reactions. 8, genetic factors such as hereditary sensory allergies. Second, local factors: skin lesions: such as anal eczema, dermatitis, venereal disease, warts, and sebaceous glands secretion of sebum, protein accumulation, fecal matter left in the skin folds around the anus, contact dermatitis caused by contact with foreign objects (animal hair, fiber, etc.). Diseases of the anorectal perineum. Hemorrhoids, anal fistula, anal papillae hypertrophy, anal sinusitis, rectal prolapse, colitis, proctitis, rectal cancer, vaginitis, urethritis and so on. Prevention of anal itching: 1, timely treatment of anal itching caused by systemic and local primary diseases, such as hemorrhoids, fistula, anal fissure, diarrhea, ascariasis, anal eczema and contact dermatitis, etc. 2, avoid eating and contact with their own allergic food, chemicals, pollen, raw paint, spicy and other stimulating foods. 3, wear underwear should not be too tight, hard to barely friction of the anus and perineum skin, do not Do not wipe the anus with chemical dyes and paper with ink, leaves of plants, etc. The toilet paper must be soft, and wash the anus with lukewarm water or 1:5000 potassium permanganate solution after stool or before going to bed to keep the skin of the anus fresh and clean. 4. Avoid anxiety and overstressing, and do not grab the skin of the anus and perineum with force to avoid scratching the skin and causing infections.