Cosmetic dermatitis is an inflammatory skin disease caused by the improper use of cosmetics and occurs mainly at the site of cosmetic application. From the pathogenesis, mainly including irritant contact dermatitis and allergic contact dermatitis, photosensitivity dermatitis and phototoxic dermatitis and cosmetic pigmentary changes. A wide range of cosmetics, according to China’s cosmetic health supervision regulations are divided into: 1, general cosmetics: including skin care, hair care, cleaning, eye cosmetics, lip cosmetics, nail cosmetics. 2, special purpose cosmetics: including hair care, hair coloring, perming, hair removal, breast, bodybuilding, deodorant, spot removal, sunscreen and other cosmetics. Clinical features: 1. history of cosmetic use 2. middle-aged and young women have a good incidence, and photosensitive lesions are mostly seen in summer. The rash mainly occurs at the site of cosmetic use, stop using the suspect cosmetics, the rash can improve, and again, can be aggravated. 3, clinical types (1) contact dermatitis: including allergic reactive and irritant two categories. Allergic reactive pathogenic factors are mainly aromatic compounds, preservatives, pigments, lanolin, lanolin and natural plant extracts in cosmetics. In China, p-phenylenediamine in hair dye takes the first place. The rash develops within 5-7 days after the first use and within 24-48 hours or a few hours after the second use, but some patients have a longer clinical time before the onset. The rash is characterized by erythema, swelling, and dense corn-like papules, papules, or blisters, which may exude. The borders are indistinct, with marked itching and burning sensation, or even stinging. The rash may fade with hyperpigmented patches, desquamation, and wrinkles. Irritant contact dermatitis is mostly chronic and cumulative, mostly caused by skin bleach, hair straightener, depilatory agent, hair conditioner, and aromatic milk cold perm, nail degreaser (containing acetone) and deodorant, detergent containing aluminum oxide, formaldehyde, etc.. Most in the repeated use of contact with the local skin gradually appear dry pale red or dark red spots, scaling and cracking, and even papules and blisters, etc., consciously dry skin discomfort, burning sensation, tingling or itching. (2) photosensitive dermatitis: divided into photomimetic contact dermatitis and phototoxic contact dermatitis. Usually in the use of cosmetics containing photosensitizers plus the onset of sunlight, mainly sunscreen agents in cosmetics such as para-aminobenzoic acid, coal tar dyes and derivatives (Lisso red, toluidine red, etc.) and perfumes, spices (cinnamaldehyde, sunflower musk, etc.) caused. The rash is limited to light-exposed areas, such as the face, V-zone on the chest, back of the hands, and manifests as erythema, papules, blisters, etc. Repeated occurrence of the rash combined with scratching and other factors can hypertrophic mossy lesions. Phototoxic dermatitis manifests itself as erythematous skin reactions followed by the formation of hyperpigmentation, individual urticaria, self-conscious itching, burning and stinging. (3) Cosmetic acne; similar to general acne, people with oily skin are prone to it. The rash is mainly follicular papules and blackhead and whitehead pimples, distributed on the forehead, cheeks and jaws. This type is mainly caused by facial cosmetics containing coal tar and other oils, lanolin, petroleum jelly, or powder particles (such as foundation creams and cover-up creams), and is especially likely to develop in women with heavy makeup. Those who have acne can aggravate the skin damage and develop a variety of dermatological symptoms. (4) Pigmented cosmetic dermatitis: Most of them are secondary to recurrent dermatitis attacks, while a few are without obvious dermatitis attacks and appear as light brown or greenish-brown pigmented spots of varying sizes with unclear edges. The pigmentation, once it appears, is difficult to fade for a long time. The pigmentation in cosmetics and preservatives are common causes. (5) Cosmetic intolerance: itching of varying degrees at the contact site, mildly with anthroposis, and in severe cases, scratching to relieve itching, partly with burning or pain. There is no obvious rash on examination, mostly seen in women with white skin. Laboratory tests: patch test or repeated open application test ROAT, repeat patch or provocative use test after a few weeks for negative patch test; for photosensitive dermatitis, a light patch test is required. Treatment principles: take a detailed medical history, identify the causative cosmetics and stop using them, wash thoroughly to remove residual cosmetics, and carry out relevant treatment according to different manifestations. 1, local treatment: erythema, papules, swelling is the main, with mild topical drugs, 3% boric acid solution, saline, with cold spray and cold film, hydrocortisone, mometasone furoate, zinc oxide, etc., but pay attention to the time and concentration of drugs, inappropriate treatment will aggravate the rash. 2, acne treatment: acne treatment is the main focus, but because it is caused by cosmetics, so the treatment must not use cosmetics again, if you want to use cosmetics, you can consider medicinal cosmetics, starting with moisturizing, can not use other or even powder cosmetics, can only aggravate the inflammatory reaction and irritation reaction. 3.Pigmented change: After this disease is produced, the treatment effect is often poor because many triggers can gradually aggravate pigmented spots, such as food, drugs, sunlight, cosmetics, toxins, endocrine factors, and it is better to use medical cosmetic technology (photon spot removal, laser spot removal), safe and efficient spot removal products. There are many kinds of spots with different reasons, so don’t treat them easily by yourself, but go to professional and regular hospitals and professional doctors for a safer and more effective treatment. 4. Systemic treatment and systematic treatment: anti-allergy, non-specific anti-allergy, individualized desensitization, application of immunomodulatory drugs if necessary. Use hormones with caution (some doctors add hormones to treatment for short-term results, which may be effective in the short term, but the end result is aggravation of the original disease and even hormone-dependent dermatitis and irreversible skin damage) With the sale of various cosmetics on the market, many sales tactics make female consumers prone to irrational consumption, irregular application, cosmetics with inaccurate efficacy, no cosmetic application Common sense, lack of experience related to beauty care, informal treatment, have brought many women very troublesome and very serious skin diseases, some are after a long time skin problems, so, cosmetology is a professional discipline, not simply a few brands, a few series, a few bottles can be explained, professional is preferred, because cosmetics to accompany your young and beautiful beautiful career, we insist never We need a beautiful latent killer, we need a true can bring us a beautiful face of the faithful partner!