Urticaria, commonly known as “rubella”, is characterized by temporary erythema or edema of the skin or mucous membranes. The common causes of urticaria in children are food, drugs, insect bites, environmental factors, but also infections (bacteria, viruses, etc.), and a certain genetic predisposition. The rash has a variety of shapes, round, oval or irregular, and can fuse into large patches. The rash comes and goes quickly and does not leave any traces after fading. Urticaria attacks may be accompanied by systemic symptoms, such as abdominal pain, chest tightness, shortness of breath and fever, indicating that the mucous membranes of the gastrointestinal tract and respiratory tract are also involved. If these symptoms are accompanied by the above, go to the hospital at any time, and in severe cases, hospitalization is required. Stay away from allergic environment, pets and allergenic food (including all seafood, mushroom, mushroom, fungus, mushroom and fungus, fruits such as cantaloupe, pineapple and mango, and avoid beef and mutton in severe cases). Avoid overheating, bathing water should be cool. Urticaria is not always curable. You can go to the hospital when you have an attack, and if you have repeated attacks, you can be tested for allergens.