Red patches on the skin, mainly due to neurodermatitis, furuncle, psoriasis and other causes, can not determine the cause of the case, it is recommended to go to the hospital dermatology department, and actively cooperate with the doctor for treatment. 1. Neurodermatitis: mainly caused by local stimulation of the skin, neuropsychiatric factors and endocrine function abnormalities, usually accompanied by intense itching, common treatment methods to drug therapy, common drugs, including fluticasone propionate ointment, oral chlorpheniramine maleate tablets and so on. 2. Hairy erythematous psoriasis: mainly caused by heredity and autoimmunity decline, it mainly occurs in the inner arm, often accompanied by the appearance of fine scales, it can be treated by taking Avicenna capsule orally and using 10% urea ointment externally. 3. Ordinary type psoriasis: It is caused by the interaction of genetic factors and environmental factors, which leads to the occurrence or aggravation of the disease. The main manifestations are scaly red spots, papules, plaques, covered with thick layers of silvery-white scales, and punctate hemorrhage can be seen after scraping off the scales, etc. It is usually treated by oral administration of Avian A capsule, immunosuppressant such as methotrexate, and topical glucocorticosteroid ointment. There are many reasons for red patches on the skin, and the performance characteristics are different due to individual physical reasons, so it is recommended to consult a hospital in time to avoid aggravation of the condition.