Neurodermatitis is a limited cutaneous nerve dysfunction skin disease also known as chronic simple moss. Chinese medicine is called “psoriasis”, “collar sores” because it is good in the neck, like the skin of the cow collar, thick and firm and named as the “Surgery Zhengzong” said: “psoriasis, such as the skin of the cow collar, tenacious hard must be firm grasp of such as rotten wood. ” The clinical features are mossy skin, thick and rough itching, a slow course, recurrent attacks often for several years, and easy to recur after healing. For common multiple skin disease, mostly seen in young people and adults, children generally do not develop. Summer more frequent or seasonal is not obvious. Etiology 1, mental factors: currently considered to be the main cause of the occurrence of the disease, mood swings, excessive mental tension, anxiety, sudden changes in the living environment, etc. can make the disease aggravated and repeated. 2, gastrointestinal tract dysfunction, endocrine system function abnormalities, chronic lesions in the body infection and allergy, may also become causative factors. 3, local stimulation: such as friction caused by too hard collar, chemical stimulation, insect bites, sunlight exposure, scratching, etc., can induce the occurrence of the disease. Neurodermatitis is a skin dysfunctional disease with obvious skin damage. It mostly occurs on the back of the neck or its sides, elbow fossa, state fossa, forearm, thigh, calf and lumbosacral area. They often appear in patches as triangular or polygonal flat-topped papules with thickened skin, raised skin ridges and deepened skin furrows, resembling moss. It is often light red or light brown in color. Intense itching is the main symptom. If there is significant damage to the skin all over the body, it is also called diffuse neurodermatitis. The first thing you need to do is to get a good idea of what you are looking for. The lesions vary in size and shape and can be surrounded by a small number of scattered flat papules; 4. The first thing is to feel the local itching, then appear clusters of corn to rice grain large normal skin color or light brown, light red polygonal flat papules, slightly shiny, covered with a small amount of chaffy scales, and then the papules fused into pieces, because of itching often scratching to stimulate the skin gradually thickened, forming mossy The skin of the affected area is often scratched around the lesions and blood crust. The skin lesions are similar to those of limited neurodermatitis, but are widely distributed, involving the head, limbs and trunk, with severe itching, especially at night, affecting sleep.