Depending on the allergy, a doctor in pediatric urgent care can help determine if there was an allergic reaction or not. In some cases, the allergen can be determined based on the symptoms and identifying what the child had been exposed to in a specified amount of time leading up to the appearance of symptoms. Using a breakdown of what the child has eaten over the 48 hours leading up to the reaction can help determine potential food allergies, while looking at a list of potential irritants they had been exposed to can determine the cause of skin reactions. Determining the exact cause of an allergic reaction would need to be done through a pediatrician. A pediatrician, or urgent care doctor, will be able to test the child on a wide assortment of potential allergens, with help from the parents on what they are exposed to, to determine which item or items are causing a reaction, as well as look at the severity of the allergy.