Dermatosis is a general term for diseases that occur in the skin and skin appendages. The skin is the largest organ of the human body, and there are not only many types of skin diseases, but also a variety of diseases occurring in internal organs that can manifest on the skin. There are many causes of skin diseases, such as skin diseases caused by infectious factors, such as leprosy, scabies, fungal diseases, bacterial skin infections, etc., often have a certain degree of contagiousness, which not only affects health, but also causes panic and social discrimination, but with the improvement of people’s living standards and scientific and technological progress, leprosy and other infectious diseases have been significantly controlled around the world. Other internal and external factors that cause skin diseases, such as mechanical, physical, chemical, biological, endocrine, immunological, etc., are now receiving more and more attention. What are the preventive matters for patients with skin diseases? 1, keep the skin clean and hygienic, try not to touch other people’s skin or towels and slippers and other personal items; avoid eating spicy, greasy and sweet food, seafood, fish, shrimp, crab, beef and mutton, wine; 2, avoid scratching, hot water washing and scalding lesions, avoid making lesions contact with soap and laundry detergent and other irritants; according to personal skin caution and safe use of cosmetics, do not blindly use; 3, avoid sun exposure, avoid eating photosensitive food and use 3, avoid sun exposure, avoid eating photosensitive food and using photosensitive cosmetics; avoid being in a continuous hot and stuffy environment; look for allergens carefully and avoid re-exposure or re-intake; 4, pay attention to skin moisturization in autumn and winter, reduce the number of baths, try to wash with water and apply olive oil after washing; pay attention to room hygiene, eliminate the insect breeding environment, and reduce skin exposure in the field; 5, pay attention to cold prevention, regular rest and rest, reasonable exercise, enhance physical fitness; keep a relaxed mood Avoid the stimulation of mental anxiety and tension; topical medication should be stopped if there is redness, swelling, pain and other signs of irritation to consult a doctor.