1. What is allergic urticaria in children? Allergic urticaria in children is a common skin disease, also known as wheals and wheals. It is caused by the body\’s allergic reaction to certain external stimuli, resulting in erythema, edema and itching on the skin. 2. What are the symptoms of allergic urticaria in children? The main symptoms of allergic urticaria in children are erythema, edema and itching on the skin. These red spots can appear anywhere on the body and vary in size and shape.