Nowadays, girls rarely go out without makeup, some girls even go out to get a courier have to apply some powder, otherwise they feel uncomfortable, girls are very enthusiastic about makeup, but they do not have enough knowledge about cosmetics, which leads to frequent illnesses. Some girls are very bold, what cosmetics dare to smear to the face, in fact, a person should do the basic makeup steps every day only: moisturizing, isolation, sunscreen, according to this step to choose cosmetics can be. Different brands of cosmetic ingredients are different, so the degree of allergy triggers are not the same, the skin is very fragile, especially now that many people are sensitive skin, so a little carelessness is easy to allergic to trigger redness, swelling, burning, so makeup as much as possible to minimize the type of cosmetics. Many girls in the purchase of cosmetics often take the fragrance intensity as a measure of cosmetic ideal or not. In fact, fragrance is only an additive used to meet people’s demand for cosmetic scents. The more complex the fragrance composition, the heavier the stimulation, and the more likely it is to cause skin allergies and photosensitivity reactions. When buying cosmetics, choose products produced by reputable and large professional companies as much as possible, and do not be tempted to buy and use products that are not labeled with the factory name, factory address, production license or production date and shelf life. Cosmetics caused by “cosmetic allergy syndrome”, the performance of the following situations: 1, stimulation reaction synthetic chemicals in cosmetics such as pigments, fragrances in contact with the skin, can directly stimulate the skin caused by erythema, papules, itching. Now some young people like black hair dyed yellow, not knowing that the peroxide in the potion and ammonia, ammonium persulfate can stimulate the scalp to increase dandruff, scalp burning pain, hair brittle and easy to break. 2, allergic reactions For some people with allergies, in the use of certain cosmetics, such as lipstick in the permanent dyes dibromo and tetrabromo fluorescein, as well as cosmetics containing lanolin various fragrances and preservatives, can cause allergic contact dermatitis. High concentrations of perfume, deodorant, hair milk in some allergic body can cause a variety of allergic reactions, and even cause spasmodic cough, allergic rhinitis, conjunctivitis, hives, etc. 3, photosensitivity reaction lipstick and other cosmetics absorb the energy of visible light, can damage the cell deoxyribonucleic acid, so that the cell mutation. Sandalwood oil, lemon oil and other photosensitive substances, applied to the skin of these cosmetics, in the sun will occur under the cell damage, causing inflammatory reactions. 4, pigmentation Some cosmetics, such as pure jasmine oil, sandalwood oil, geranium oil, etc. can cause some women to appear “pigmented cosmetic dermatitis”. The manifestation is a diffuse, or patchy light brown pigmentation on the cheek or forehead, sometimes with mild erythema or papules, itching. Here we remind the girls who use cosmetics, first of all, read the instructions carefully and use according to the instructions, but also a small amount of cosmetics applied to the inside of the forearm, and so 24 hours later to observe any adverse reactions before use, such as reactions are prohibited, should not use imported cosmetics without Chinese labels.