Allergic reactions are a relatively young and marginal discipline, and there are still few people specializing in allergic reactions in China, and people do not know enough about it. Our allergic reaction clinic was established in 1964, which is one of the early hospitals in China to establish allergic reaction clinic. Allergic reaction (allergy) is a coined word, consisting of the Greek words allos (strange) and ergon (reaction), which means abnormal reaction. Allergic diseases are also known as allergic disorders, which are characterized by an excessive immune response to one or more normally tolerated substances in the environment, resulting in damage to tissues and organs, and thus affecting normal physiological functions. The World Allergy Organization conducted an epidemiological survey of allergic diseases in 30 countries, and the results showed that 22% of the total population of l2 billion in these countries suffered from immunoglobulin E (IgE)-mediated allergic diseases, such as allergic rhinitis, asthma, conjunctivitis, eczema, food allergy, drug allergy and severe allergic reactions, etc. The increase of these diseases is related to long-term and continuous environmental factors and lifestyle changes. lifestyle changes. In the process of urbanization and industrialization, the yearly increase of automobile exhaust and air pollutants in heavy industrial cities have a strong local stimulation on the nasal mucosa, throat mucosa and respiratory tract mucosa, triggering allergic reactions in the body, resulting in a significant increase in the incidence of allergic respiratory diseases such as allergic rhinitis, asthma and allergic pharyngitis. Allergic diseases have their natural course (atopic march): that is, at a specific age, the characteristic clinical manifestations of allergic reactions appear successively. The majority of allergic patients tend to show food allergy, eczema, vomiting, diarrhea, etc. during infancy and early childhood; after the age of 4-5 years, they gradually become allergic to inhaled allergens and develop respiratory allergy symptoms such as nasal congestion, runny nose, coughing and wheezing. Parents may have a high suspicion that their child has allergies based on the following circumstances: Family history of allergic diseases Eczema as a child increases the chance of developing other allergic diseases as a child Every cold is accompanied by wheezing Chronic coughing, especially in the middle of the night and early in the morning Sneezing continuously in the morning after waking up, sometimes running nose, feeling phlegm in the throat Rubbing the nose, feeling itchy nose, nasal congestion, itchy eyes, especially Coughs violently after exercising or eating cold food, especially in winter or summer when sweating