Children's allergies are mostly related to the immune system. When the baby's immunity is low, it is easier to be allergic. Therefore, to improve the allergic constitution, the most fundamental thing is to enhance the baby's immunity. The following points should be paid attention to in strengthening physical fitness: 1. Let the baby exercise more, enhance his physical fitness and exercise more, which can increase cardiopulmonary function, promote blood circulation and enhance immunity, such as swimming and running. If it is a baby, moderate crying can also increase cardiopulmonary function, which belongs to exercise. 2, can not be picky eaters, partial eclipse, usually pay attention to good eating habits, pay attention to a reasonable diet. 3. If necessary, drug supplements can be given, such as Xiaoshikang and Huangqi Granules.