At present, the department carries out patch test, in vitro allergen test, food intolerance, prick test and Baikang allergen test to meet the detection of allergens for different patients and different conditions, and to help patients find possible causes to prevent recurrence as much as possible. 1, patch test is a professional detection of chemical allergen detection method, is the most reliable and simple method to diagnose contact dermatitis, adapted to facial dermatitis, hand eczema, contact dermatitis, occupational dermatitis, cosmetic dermatitis, chronic urticaria, etc.. For long-term or recurrent dermatitis of the face, hands, legs, feet and other parts of the dermatitis, should be patch test to find the cause. 2.In vitro allergen testing is done by taking a small amount of blood and detecting the specific IgE produced by certain allergens in the serum to complete the detection of specific allergens. This test is mainly for patients with rapid allergic reactions, and only a small amount of serum is needed to easily detect allergens. It is especially suitable for children, those who have been treated with systemic medication and those who are not suitable for dot prick test such as generalized skin lesions. 3, the detection of food intolerance Food intolerance refers to a complex metabolic disease. The human immune system treats one or more kinds of food entering the body as harmful substances, thus generating excessive protective immune responses against these substances and producing food-specific IgG antibodies, which form immune complexes with food particles (type III metamorphosis) and can cause inflammatory reactions in all tissues (including blood vessels) and manifest as symptoms and diseases of various systems of the body. The 14 tests commonly done for food intolerance include: beef, chicken, cod, corn, crab, egg, mushroom, milk, pork, rice, shrimp, soy, tomato and wheat. This combination is based on a large number of clinical epidemiological statistics. The test requires only 1 ml of blood to be drawn. A normal diet can be consumed before the blood is drawn and no special requirements are needed. The test is performed using an enzyme-linked immunosorbent assay (ELISA). The test results indicate whether the subject is intolerant to a particular food and the degree of intolerance (mild, moderate or severe). The doctor can give the correct dietary advice accordingly. If the patient is allergic to the allergen, a red swelling similar to a mosquito bite will appear at the site within 30 minutes; this test is mainly used for patients with rapid allergic reactions such as urticaria, atopic dermatitis, allergic rhinitis, allergic bronchitis, allergic asthma, allergic conjunctivitis, etc. Conjunctivitis and other allergic diseases. The spot test is recognized as the most convenient, economical, safe and effective allergen diagnosis method in European countries and the United States. 5.BICOM biological resonance detection of allergens BICOM uses resonance effect to detect whether different substances can cause specific frequency changes in the body to identify allergic substances, i.e. allergens. Detection is convenient, no blood sampling, no pain.