Patient: Hello, Director! My child is 4 years old and she has been getting hives on her buttocks lately, and she had eczema when she was 2 years old. Sometimes, I don’t know if it’s because of diet or smell, but she starts sneezing and sniffing. I would like to know what is causing it. Is there any test that can find out? Professor: Hello! From your description, your child probably has not only hives but also allergic rhinitis. Food is the main cause of hives in children, and it is especially important to determine which food allergies are present. Keep a record of the types of food eaten each month such as rice, eggs, shrimp, chicken, cucumbers, tomatoes, etc., the time of ingestion, and when the hives occur – keep a record. Once hives occur, you can find out the relationship between food and hives from the records. Generally, more attention should be paid to the food eaten 12-24 hours before the onset of hives. This method is simple and easy to master, but it is more difficult to get accurate results. Allergic rhinitis, on the other hand, is closely related to inhaled gases or odors. Therefore, allergen screening through skin prick in the hospital can know both the food that causes allergy and the odor or dust or pollen that causes allergy inhalation.