Children’s lips suddenly swollen to pay attention to the following situations: 1, carefully ask the medical history, check the lips to see whether the trauma caused by hematoma in the lips. 2, pay attention to the allergic situation, if the contact with allergens or intake of allergy-prone food, there can be a neurovascular edema, manifested in the sudden swelling of the lips, and usually there may be other skin rashes, etc. 3, pay attention to the sudden swelling of the lips may be due to gum redness and swelling, oral inflammation. It may be due to gum redness, oral inflammation. 4, if the sudden swelling of the lips is accompanied by other clinical symptoms, such as recurrent fever, cough, runny nose, vomiting, diarrhea, etc., but also pay attention to the impact of their own disease, if it is a highly sensitive body viruses, bacteria itself, as well as taken, the use of the drug can also make the child appeared neurovascular edema caused by sudden swelling of the lips.