Solar dermatitis, or solar dermatitis, also known as sunburn or sun spot, is an acute inflammatory reaction to normal skin after exposure to sunlight, manifesting as erythema, edema, blistering and hyperpigmentation, and desquamation. The intensity of the reaction is related to the intensity of light, duration of exposure, individual skin color, body type, race, etc. It is more common in late spring and early summer, and is more common in children, women, skiers and water workers. Etiology The light spectrum is mainly UVB. Normal skin is exposed to UV radiation to release histamine, 5-hydroxytryptamine, kinins and other inflammatory mediators from a variety of cells in the dermis, causing vasodilation and increased permeability in the dermis. Clinical manifestations After a few hours to more than ten hours of sun exposure in spring and summer, erythema with clear boundaries appears on the exposed area, bright red, and in severe cases, blistering and vesicles may appear; subsequently, the color of the erythema becomes darker and flakes off, leaving pigmentation or hypopigmentation. Self-conscious burning or tingling sensation, often affecting sleep. In mild cases, it heals within 2 to 3 days, but in severe cases, it takes about a week to recover. Individual patients may develop conjunctival congestion and eyelid edema. If the sunburn is extensive, it may cause systemic symptoms such as fever, chills, headache, fatigue, nausea and general discomfort, or even palpitations, delirium or shock. Diagnosis is generally not difficult based on local skin erythema, edema or blistering after sun exposure, leaving pigmentation spots after healing, and self-conscious burning and painful sensation. Treatment 1.Systemic treatment The lighter cases are treated with antihistamines, while the heavier cases or those with poor efficacy are treated with oral small doses of glucocorticoids, aspirin or indomethacin. 2.Local treatment: Local topical application of glyburide lotion in mild cases, cold compresses, glucocorticoid cream or 2.5% indomethacin solution in slightly severe cases. Avoid sun exposure and pay attention to protection when going out, such as holding an umbrella, wearing a wide-brimmed hat and wearing long-sleeved clothes; if outdoors, it is recommended to routinely apply sunscreen with SPF 15 or higher, and those with severe photosensitivity need to use high-efficiency sunscreen with SPF 30 or higher. SPF30 or higher high-efficiency shading agent.