Allergen detection has the following methods: 1, patch test: that is, collect some allergens in small doses in a special container, generally in a circular grid of reagents, such as 40 or 60, and then put the reagents on the back, observe the skin reaction every 24 hours or 48 hours, and compare the standard comparison card to determine whether it is positive, strong positive or negative, patch test is the most direct; 2, blood sampling test: generally More than 20 kinds of common inhaled or ingested allergens can be detected; 3. Bio-wave therapy: It is said that thousands of allergens can be detected, but it is recommended to use patch test or blood sampling to check allergens. The patch test requires an interval of 24-48 hours before the results are available, while the blood test is usually drawn in the morning and the results can be seen in the afternoon. The point of allergen testing is to know what you are allergic to and to avoid contact with or ingestion of such allergens; however, for acute, episodic allergies, the test is slightly less cost-effective.