Allergy is a common phenomenon in our life, and its triggering causes are more complex and may be related to genetic factors, food, drugs, ultraviolet rays, etc. According to the clinical manifestations, it can be divided into mild allergy, moderate allergy and severe allergy. Patients with severe allergy may cause obstruction of the whistling tract, resulting in chest tightness and breath-holding symptoms. When allergies occur, what we should do is to go to the hospital as soon as possible to find the allergens. Common allergens include: inhalants; ingested substances (fish, shrimp, milk, etc.); drugs; mosquito bites, animal fur, etc. If it is a food allergy, stop the intake of such food; if it is a cosmetic allergy, stop using cosmetics, and then use anti-allergy drugs, orally or topically. In addition to finding the source of allergy, avoiding its reappearance and active medication, you also need to do the following: First, during the period of facial skin allergy, do not wash your face with too hot water, so as not to stimulate the skin, and do not use soap and soap and other alkaline items, otherwise it will aggravate the symptoms of skin allergy. Second, skin allergy daily regimen should pay attention to regular life, maintain adequate sleep; skin should be kept clean, often wash your face with cold water and avoid excessive sun exposure. Third, do not eat spicy fried food during the allergy period, usually eat light, also do not eat food that can easily cause allergies, such as wine, seafood, etc., eat more fresh vegetables or fruits, avoid some high oil and high calorie food, diet as light as possible. Fourth, all cosmetics should be stopped during the allergy period to give the skin a buffer time. If a person has recurrent allergies, then it is necessary to identify the allergen and avoid contact with it, which is currently the most effective way to prevent allergic reactions from occurring. If contact cannot be avoided, desensitization can be tried, but it takes longer and is 80% effective, and some desensitization treatments may be ineffective. People who are generally weak are prone to allergies, so it is important for people with allergies to always take care of themselves and strengthen their constitution.