(Abstract) OBJECTIVE: To observe the efficacy of self-prepared CangShan lotion in the treatment of perianal eczema. Methods: 50 cases of perianal eczema of the damp-heat-infused type were treated with the self-prepared CangSkin lotion as the basic formula. Results: 40 cases were cured, 6 cases were improved and 4 cases were invalid, with an efficiency of 92%. Conclusion: The treatment of perianal eczema with self-prepared CangShan lotion was effective. Perianal eczema is a common allergic skin disease in anorectology. Its lesions are mostly confined to the skin around the anus, and occasionally spread to the buttocks, perineum and clitoris, with local flushing, rash, erythema, vesicles, blisters, exudation, crusting, desquamation, intense itching or rough lesions, hypertrophy, moss-like changes, pigment loss, radial skin cracking as the main clinical manifestations, and can develop at any age. It is a common allergic disease, called “dip sores” in Chinese medicine, but now it is uniformly called eczema. Modern medicine believes that the causes of eczema are complex, but it is generally believed that there is a relationship with allergic reactions. The incidence is high, prone to recurrence, seriously affecting the normal work and life of patients. Modern medicine treats the disease with antihistamines and corticosteroids, which can control symptoms but can cause adverse reactions (such as drowsiness, dizziness, skin atrophy, corticosteroid-dependent dermatitis) with repeated long-term application and easy relapse after healing. Chinese medicine has a long history of treating this disease, with many methods, rich experience, certain efficacy and few side effects, so it is increasingly favored by the majority of patients. In clinical treatment, our department has developed its own fumigating bath for anal eczema of the damp-heat-infused type, which has good efficacy and also shows good clinical application prospects because of its low toxic side effects. The relevant reports are as follows: 1. Information and methods 1.1. Diagnostic criteria: The 50 cases in this group were all outpatient records, including 36 male cases and 14 female cases, aged 86 years old at the maximum and 20 years old at the minimum, with clinical manifestations of flushing, rash, erythema, vesicles, blisters, exudation, crusting, desquamation, intense pruritus or rough lesion area, hypertrophy, moss-like changes, pigment loss, radiation-like The main clinical manifestations are skin cracking, etc. Some patients are accompanied by anal sphincter relaxation and anal overflow. 1.2. Treatment: Advise patients to lead a regular life, avoid stimulating or allergic food, and avoid scratching when exudate appears. Give one dose of self-prepared CangShan lotion daily, decocted in water to obtain 3000 ml of juice, first smoked, and then sit in the anal area for 15 minutes when the temperature of the juice drops to about 35 degrees Celsius, twice a day. The formula is as follows: Cang Zhu 30g, Di Di Zi 30g, Cang Er Zi 15g, Huang Bai 30g, Bitter Ginseng 30g, Tu Fu Ling 15g Raw Rhubarb 15g, Huang Lian 15g, Comfrey 15g, Wu Bei Zi 15g, White Moss Bark 15g, if the anal sphincter is relaxed and the anus overflows, Wu Bei Zi increase the amount to 30g, see Furfuryl as appropriate to astringent itch. 1.3. Typical case Patient Li, male, 65 years old, mainly due to perianal itching with dampness for two years, presented with perianal itching without obvious cause two years ago, and the symptoms improved after topical treatment with paregoric pine, after which recurrent episodes persisted. At the time of consultation, the skin around the anus was flushed, with obvious lesions, roughness, hypertrophy, pigment loss, radial skin cracking, and moist surface with exudate. There were scratch marks. After one week, the exudate improved significantly and the itching was not obvious. No recurrence after three months of follow-up. 1.4. Criteria for determining the efficacy According to the Chinese medicine industry standard of the People’s Republic of China “Diagnostic Efficacy Criteria for Chinese Medicine Dermatological Symptoms”: cure means complete disappearance of skin lesions, good for 30% remission of skin lesions, and ineffective for less than 30% remission of skin lesions. 2, results After three courses of treatment, 50 patients were cured in 40 cases, improved in 6 cases and invalid in 4 cases, with an efficiency of 92%. 3. The onset of damp sores is mostly due to congenital deficiency of endowment, dietary disorders, or excessive consumption of spicy and stimulating meat and fishy things that move the wind, damage to the spleen and stomach, loss of healthy transportation, internal production of damp heat and external exposure to wind evil, and internal and external wrestling between the two evils, resulting in wind-damp-heat evil infiltrating the skin. It can develop at any age. Modern medicine divides eczema into acute and chronic phases. Acute eczema: Acute eczema generally follows the process of flushing – papules (maculopapular rash) – blisters (exudation) – vesicles – crusting (scaling) – pigmentation of new growth, accompanied by itching. The clinical manifestations are marked plasma exudation, or in strict cases, dripping exudation, intense itching that is difficult to tolerate, scratching that results in scratches, hemorrhagic crusts, and combined bacterial infections that result in pustules, purulent exudates, and purulent crusts, presenting the characteristic appearance of eczema, i.e., multiple types of rashes exist simultaneously. The itching is particularly intense in acute eczema, and fecal contamination is more likely to cause bacterial infection, which can extend to the perineum, scrotum and buttock skin, affecting the patient’s life and work, making the course of the disease extremely unstable and prolonging the treatment process, and turning it into a chronic process. Chronic eczema: chronic perianal eczema is more common than acute eczema, with local manifestations of skin thickening, tinea changes, creases and fissures, tendency to exude, intense itching, chronic, easy to recur. Chinese medicine treatment is appropriate to clear heat and dry dampness, cool blood and stop itching, so this formula is used. Atractylodes macrocephala, Dictyostelium, dampness, stop itching; Phellodendron, Huang Lian, bitter ginseng to clear heat and dampness; Cang Er Zi to dispel wind and dampness, stop itching; White Moss Peel, Tu Fu Ling to clear heat and detoxify, remove dampness and stop itching; Raw Rhubarb, Comfrey to clear heat and detoxify and cool the blood; Wu Bei Zi to astringently stop diarrhea and astringent. During the medication period, avoid eating spicy, fish and shrimp, chicken, goose, beef, mutton and other hairy products, onion, ginger, garlic, cilantro, leek, celery and other spicy products. Avoid scratching the area to prevent infection.