Allergic babies generally do not have obvious symptoms when they are not exposed to allergens, but if they are exposed to allergens, they may develop symptoms such as itchy skin, redness, swelling, nausea and vomiting, as well as nasal congestion, runny nose, sneezing, etc. Allergic babies are more prone to allergic reactions. Allergic babies are more prone to allergic reactions, such as contact with airborne dust mites, pollen or eating allergy-prone foods and medicines may lead to allergic symptoms, such as red, swollen, itchy and painful skin, or nausea and vomiting, abdominal pain and other reactions, but also nasal congestion, runny nose, sneezing and other respiratory symptoms may occur. If your baby has already had an allergic reaction, you need to use anti-allergy medication under doctor’s supervision, such as loratadine, cetirizine, etc., so as not to aggravate the allergic reaction.