The hot summer sun with its relentless UV rays damages our skin. In mild cases, the skin is tanned, spotted and wrinkled, while in severe cases, burning pain, red spots and blisters appear on the face, neck, arms and other exposed areas. This is the time to be alert to the occurrence of solar dermatosis. According to the wavelength of sunlight, sunlight can be divided into ultraviolet light (180~400nm), visible light (400~760nm) and infrared light (760~1800nm). UV rays can reach the basal layer of the epidermis and cause epidermal necrosis and hyperpigmentation by strong irradiation, thus causing heliodermatosis. How can we prevent the occurrence of solar dermatosis in our daily life? 1, should avoid exposure to the sun, in exposed areas pay attention to the external use of physical shading agents or chemical shading agents, such as titanium dioxide cream, benzophenone, etc.; 2, some photosensitive foods and drugs have photosensitizers, even if you are not allergic to sunlight, after taking these photosensitizers can cause solar dermatosis. Photosensitive foods such as mud snails, carrots, parsley, spinach, fresh fungus, celery, etc., Chinese herbal medicine Angelica dahurica and bone marrow also have photosensitizers, drugs such as tetracycline and quinolone antibiotics contain photosensitizers; 3, avoid going out at noon, 11 a.m. to 3 p.m. is the strongest period of ultraviolet light. SPF refers to the ability of sunscreen products to prevent medium-wave ultraviolet rays, the higher the value means the stronger the protection effect, internationally, SPF value 2~4 is the lowest sun protection effect, 6~8 is the medium sun protection effect, 8~15 is the higher sun protection effect. PA value indicates the function of sunscreen products to prevent long-wave ultraviolet rays, with prevent skin tanning, aging function; 5, serious condition, need to seek medical help, the principle of treatment to anti-inflammatory, soothing, pain relief. General external use of glyburide lotion and glucocorticoids, can have 3% boric acid water or milk wet compresses, with systemic symptoms to take antihistamines, vitamin C, serious can not control the person to take glucocorticoids under the guidance of a doctor.