In outpatient clinics and website consultations, we often encounter many people who suffer from sudden appearance of erythema, swelling, peeling, even blistering, itching and pain on their facial skin, which affects their beauty, life and work. They are desperately looking for the cause and treatment. The following are the causes and treatments that may cause acute dermatitis that I encounter in my daily medical work: Possible causes of acute dermatitis on the face: 1. Sun dermatitis, sunburn: facial skin is the part of the body that receives the most sunlight and the longest time. So it is more common. Itself is sensitive to ultraviolet light, and too long exposure to sunburned skin, mostly occurs in the direct light parts. It is more likely to occur in people with fair skin and less outdoor activities. Skin performance large red spots, blisters, scratching, pain, serious headache, fever. 2, cosmetic dermatitis: cosmetics are clinically tested and are safe for most use, so they can be sold in the market. However, there are people who are allergic to some of the ingredients, especially to the perfumes, fragrances, hair dyes, etha-midazolam, melanin and other ingredients, more allergies occur. This is also because the fragrances are exposed to light and phototoxic reactions occur, stimulating the skin to cause dermatitis. So in the choice of cosmetics as far as possible to choose not contain or less fragrance. 3, contact allergic dermatitis: facial skin direct contact with certain external substances and caused by skin inflammatory changes. Anyone exposed to strong acids, strong bases and other toxic substances can cause dermatitis called irritant (toxic) contact dermatitis. Only a few people with allergies are exposed to certain substances that cause dermatitis mostly called allergic dermatitis. Allergic substances can be contact with volatile gases such as gasoline, aldehydes, benzene, ethers, mustard gas, and even pollen, airborne floating substances, etc. There are toxins from animals, poisonous hairs from insects, etc. It can also be an indirect way, through the hands, towels and other allergens to the face to cause allergic dermatitis. 4, photosensitive dermatitis: intake of photosensitive substances in the body, such as food: white radish, spinach, celery, ashwagandha, marjoram, horsetail, lettuce, potatoes, parsley, amaranth, rape, tomatoes, eggplant, purple cabbage, snails, capers, leeks and other fruits such as papaya, figs, mangoes, lemons, etc. Such as drugs: hematoporphyrin, sulfonamides, chlorpromazine, promethazine, thiazides, tetracycline family, ashwagandha, dahurica digestion and absorption of photosensitive substances into the blood to the skin, and then after ultraviolet radiation, the production of phototoxic substances cause inflammation of the skin at the site of exposure to light. The onset is mostly in young and middle-aged people, followed by the elderly, more women than men, and more in spring and summer than in autumn and winter. The clinical manifestations of facial dermatitis: The initial manifestations of lesions are varied, often related to the form, appearance, and manner of exposure, and are commonly erythematous, ranging in size from small flakes to large areas of redness and swelling, and even the disappearance of eye fissures. Highly allergic people can appear blisters on the erythema, and vesicles can also appear after the blisters break, and ooze. Dermatitis occurring in direct sunlight areas is mostly caused by allergy to light or prolonged exposure. Ingestion of photosensitive foods in the body, drug rash also manifests as erythema, blistering, and polypoidal sun rash on the skin at the site of light exposure. If the facial dermatitis manifests as irregular patches, what caused the allergy may have been brought to the face through the hands or other objects causing the dermatitis. If not treated early, it can become subacute or chronic. The skin becomes thickened and hyperpigmented. How to deal with facial dermatitis urgently? The first step is to stop using facial cleansers, cosmetics, and skin care products. and items suspected of causing facial dermatitis related. Avoid irritating foods, overheated environments, and mechanical irritation. If dermatitis occurs within 1 to 2 hours, you can immediately rinse with water, or use light saline, saline, or 3% boric acid water as a cold wet compress. Secondly, if the dermatitis is found to appear for more than 4 hours, the treatment and medication should be selected according to the different performance of the lesions. Erythema phase: mostly early, can be accompanied by swelling, regardless of the size of the area, you can use the cold wet compress method. See my article (Learn how to apply wet compress treatment) for specific methods. In the case of blisters, vesicles and oozing, cold wet compresses can also be applied first, followed by topical application of water powder and creams with soothing, protective, anti-inflammatory and anti-itch effects. In cases of erythema with varying degrees of hypertrophy or formation of mossiness, low to medium strength corticosteroid creams can be used. Avoid hot water washing and mechanical stimulation. Thirdly, if the disease is serious and develops and spreads rapidly. Systemic medication, antihistamines, or injection of 10% calcium gluconate, 10% sodium thiosulfate, or hydrocortisone drip, etc. are needed. Or urgently go to hospital for treatment. For people with allergies, such as solar dermatitis, photosensitive dermatitis, prevention is especially important, not to go out when the sun is strong, take protective measures outside, play umbrella, wear a hat, wear a long shirt, for hypersensitive people to apply sunscreen is also extremely.