Sunburn is an acute phototoxic reaction of the skin caused by excessive exposure to sunlight (mainly UVB). Ultraviolet rays include UVA (wavelength 320-400nm) and UVB (wavelength 290-320nm). UVA accounts for about 99% of the ultraviolet rays that actually reach the ground through the barrier of the atmospheric ozone layer, and UVB accounts for about 1%. UVB not only causes edema, erythema and other inflammatory reactions, but also leads to skin aging and even increases the risk of skin malignancies. Acute sunburn reactions can be as mild as redness of the skin, which can be accompanied by pain and itching, or as severe as redness, blistering and peeling, the latter often leaving intractable sun spots after recovery. Long-term chronic sunburn reaction can aggravate the original skin pigmentation lesions such as freckles and melasma, and can also lead to photoaging of the skin, manifested as skin discoloration formation, pigmentation, capillary dilation, skin roughness, coarse skin lines, decreased elasticity and fine lines formation. Acute sunburns require immediate and appropriate repair methods to promote skin recovery and reduce after-effects. If the skin is only slightly red, rinse with cool water, gently remove all facial cosmetics, cool down the skin temperature and then moderately apply some hydrating spray, its symptoms will be quickly relieved; if accompanied by scratching, pain, and even redness, rashes and other sensitive symptoms, the sunburn is more serious, in addition to cooling and calming the skin measures, you need to choose to use some of the better after-sun repair products on the market, including a calming If the redness and sensitivity are more serious, you need to consult a doctor in a hospital and use anti-allergic medicines together. Overall, what is needed most in the acute period after sun exposure is cooling and calming, hydration and moisturizing. Here are a few more practical methods that I hope will be of some help to you. 1, the spray will be placed in the refrigerator to refrigerate, take out directly sprayed on the face or other sunburned parts, or sprayed on the mask paper cold compress, have a calming and soothing and reduce the role of skin temperature. 2, cucumber juice or cucumber slices on the face: rich in Vit C, for skin hydration, is a natural whitening good, and not easy to occur allergic phenomenon. 3, lotion or mask containing aloe vera: aloe vera has a calming and anti-inflammatory effect, but it is not recommended to use the original juice and pulp to avoid causing allergies. After recovering from serious sunburn, it is often difficult to treat sun spots, presenting large brown spots or in the shape of flower spots. In the short term, some whitening skin care products and whitening masks can be applied intensively, expecting to remove or lighten sun spots early, and those who cannot recover completely after half a year can consider photorejuvenation or other treatments, but the effect is often not ideal. Photoaging caused by long-term chronic sun damage can be better improved by photorejuvenation. The way to prevent sunburn is to minimize the time spent in the sun, avoid strong ultraviolet rays as much as possible, and develop good habits of sun protection, regardless of spring, summer, autumn, winter, sunny or cloudy days, and to apply sunscreen, and to apply sunscreen products marked with water-resistant words when swimming. Of course, sunscreen is not a panacea, umbrellas, hats, sunglasses and clothing are also essential protective measures. Our skin will remember every sunburn, which will not only lead to skin aging and discoloration, but will also increase the risk of skin malignancies later on.