知道什么时候该去看医生。 妥善处理水疱。 考虑使用磺胺嘧啶银乳膏。

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Most cases of sunburn are classified as first degree burns, which can be treated at home with the above advice and staying out of the sun for awhile. However, extreme sun exposure can also cause second and third degree burns, which need medical attention and treatment. Second degree sunburn is characterized by blistered and wet looking skin, redness and damage to the entire epidermis and upper layers of the dermis. Third degree sunburn is characterized by flayed and dry looking skin, dark red or ashen color and destruction of the entire epidermis and most of the dermis. Skin sensation is usually diminished with third degree burns.  Second degree sunburns heal within 10–21 days, typically without any scarring. Third degree sunburns often need skin grafts to heal and always leave scarring.  Other reasons to see a doctor after a sunburn include symptoms of dehydration (see above) or heat exhaustion (heavy sweating, faintness, fatigue, weak but rapid pulse, low blood pressure and headache).  For children, as a general guideline, seek medical attention if a blistering sunburn covers 20% or more of their body (a child's whole back, for example). . Moderate-to-severe sunburn typically involves skin blistering, which is a natural protective reaction of your body. If you notice blisters form on your sunburned skin, don't pick at them or break any. Blisters contain your natural body fluid (serum) and form a protective layer over the burned skin. Breaking blisters also increases the risk of infection. If you have minimal blistering on accessible body parts (like your forearms, for example) then cover them with dry, absorbent bandages. However, if you have lots of blistering and its on your back or other inaccessible areas, then get your doctor to care for them. Your doctor will likely apply some antibiotic cream and dress the blisters properly with sterile bandages to limit the risk of infection, minimize scarring, and promote healing.  Change the bandages one to two times daily (if accessible), but remove them...