Neurodermatitis, or chronic simple moss, is a common chronic cutaneous neurological dermatosis; it manifests as pruritus and flaky flat papules. The etiology of this disease is still unclear and may be related to neuropsychiatric factors. The main causative factors are neuropsychiatric factors (such as anxious temperament, excessive thinking, stress, depression, fatigue, poor sleep, etc.), gastrointestinal dysfunction, endocrine disorders, diet (such as alcohol, spicy food, fish and shrimp, etc.), local stimuli (such as hard collars, woolen fabrics, chemical substances, infected lesions, sweat impregnation, etc.). The vicious cycle of itching – scratching – itching formed during the course of the disease is the main cause of the progression of the disease and leads to rash. Clinical manifestations: The disease mostly affects young and middle-aged people, and is rare in the elderly and children. It occurs most often on the neck, collar, upper eyelids, but also in other areas such as the lumbosacral region, ankles, etc. It is mostly confined to one or both sides symmetrically distributed. The basic lesion is a skin-colored, light red or light brown polygonal flat papule, the surface may be covered with thin layer of scales, the lesion gradually fused and expanded, forming moss-like changes, the central lesion is large and obvious, the edge can still be seen scattered flat papules, the boundary is clear; paroxysmal pruritus, often intensified by local irritation, mental irritability, obvious at night; the lesion and its surrounding common scratch or crust, but also due to the improper use of topical drugs and Contact dermatitis or secondary infection may occur due to improper use of topical medications. The disease is chronic and does not heal for years or recurs, and is generally heavy in summer and light in winter. This disease is mainly treated with topical medication, and the type of medication (antipruritic, tar or glucocorticoid) and dosage form should be reasonably selected according to the type of lesion, location and season of onset; glucocorticoid ointment can be used to seal the treatment for mossy lesions; external Chinese medicine, skin needling and fire canning can also be given. If itching is severe or the effect of topical drugs is not good, antihistamines can be used. If it cannot be controlled, sedative and sleeping drugs (such as diazepam or doxepin) can be added after dinner or at bedtime, and procaine intravenous closure can be used for severe cases. Fourth, prevention: regular life, pay attention to rest, do not overwork; avoid all kinds of stimulation, if necessary, allergen testing, supplemented by psychotherapy to interrupt the vicious cycle of itching ~ scratching ~ itching.