In general, if the child does not have any clinical symptoms of possible allergy, it is not necessary to check for allergens. If a child has clinical allergies or highly suspected allergy symptoms, allergen screening should be done, usually seen in the following cases: 1. If the child has frequent rashes, especially recurrent and itchy hives, allergen testing should be done. 2. Some children have symptoms of gastrointestinal allergies, such as recurrent diarrhea, blood in the stool, abdominal distention, and abdominal discomfort. 3. Children with chronic possible allergic rhinitis symptoms such as frequent runny nose and sneezing, or frequent coughing, shortness of breath, and recurrent respiratory infections may also have allergies and need allergen testing as well.