There are various ways to check allergens, the most common ones are prick test, blood test and patch test. 1. Prick test is to put the skin test solution on the skin, and then use a needle to gently pierce the epidermis, if the skin appears red spots, edema, or wind, it will be positive, indicating that the antigen is allergic to the antigen. 2. Blood test. The blood test can detect the level of IgE antibodies. About 5 ml of blood is collected from a vein. 3. The patch test is a test in which a suspected allergen is placed on the skin for a certain period of time and the skin is observed to see if there is any reaction to determine whether or not there is an allergy. For people who are allergic to allergens, they should pay attention to a balanced diet, eat less greasy, sweet and stimulating foods, and stop smoking and drinking. Eating more vitamin-rich foods such as fruits and vegetables can enhance the body’s immune system. Allergy patients need to pay attention to avoid allergenic foods and other allergens, drink more water, and keep a relaxed mood.