Xiao Wang is 23 years old and has had recurrent episodes of itchy nose, sneezing and clear nasal discharge for 3 years. Recently, he has also developed nasal congestion and often goes to the pharmacy to buy some cold medicine once he has an episode, and then his symptoms recur after a few days. Recently, Xiao Wang resolved to go to a large hospital, wanting to thoroughly investigate what is the disease. The doctor, through a physical examination, considered that it might be allergic rhinitis and suggested that Xiao Wang check the allergens. Wang was reluctant and asked: What is the use of knowing the allergen even if someone has said so? Through the doctor’s patience, he agreed to check allergens in the afternoon. After taking blood tests, Wang was found to be allergic to mites and milk. Through good hygiene and mite cleaning, no dairy products, and medication, Wang’s symptoms were soon stabilized and effectively controlled. Allergen testing is a necessary test to confirm the diagnosis of allergic rhinitis. After knowing the allergens, one should try to avoid contact with them, and food allergens must be stopped, together with medication, in order to better treat allergic rhinitis.