What do people with photosensitivity need to pay attention to in their daily lives? When the spring is bright and sunny, some people suffer from so-called “photoallergy” phenomena such as redness, flaking and itching on exposed areas, especially on the face. In fact, there is no such term as “photoallergy” in medicine. Some patients may be phototoxic reaction, that is, sunburn, mainly induced by medium-wave ultraviolet (UVB), manifested as erythema, edema, clear boundaries, avoiding the light can gradually subside, and then leave obvious hyperpigmentation. More patients may have photomorphic reactions, mainly induced by long-wave ultraviolet light (UVA), manifesting as erythema, papules, wheals, blisters, vesicles, and desquamation with itching symptoms. Photosensitivity tests and patch tests can help to identify the causative spectrum. Since ultraviolet light is the main culprit of “photoallergy”, and ultraviolet light is almost “omnipresent and ubiquitous”, therefore, no matter in spring, summer, fall or winter, ultraviolet light protection is essential, especially for those who are prone to “photoallergy”. The people who are prone to “light allergy”. 1, physical sunscreen: daytime activities in the outdoors, should wear a wide-brimmed hat and sunglasses, wear darker color long-sleeved clothes. 2, external sunscreen: due to UVA and UVB damage to the skin, so sunscreen should choose both, that is, at the same time have SPF and PA logo sunscreen; daily care selection SPF15 ~ 20/PA + + + sunscreen can be; in the sunbathing and travel in tropical areas, you need to SPF30/PA + + + + and above the protection index of the sunscreen; due to the decomposition of the effective substances, perspiration and other reasons, sunscreen is not a good choice. Due to the decomposition of effective substances, sweating and other reasons, sunscreen needs to be reapplied every 2 hours 1 time. 3, more food containing vitamin C, vitamin E food to help reduce the phenomenon of light allergies, while avoiding the consumption of some photosensitive foods such as mud snails, snowdrops, lettuce, amaranth, capers, celery, spinach, parsley, figs, oranges, lemons, mango, pineapple and so on.