A swollen mouth can cause a lot of inconvenience and affect daily life. But in fact, it is easy to reduce the swelling quickly, as long as the cause of the swollen mouth is found and then treated symptomatically. Angioedema is the most common type of mouth swelling, and since the disease is caused by allergies, it should be treated by first clarifying the allergen and avoiding re-exposure to the allergen, and it can be cured by applying some anti-allergy drugs appropriately. If the allergen is not clearly identified, it can still recur when the allergen is contacted again. It should be noted that when the edema occurs in the epiglottis, prompt medical attention should be sought to avoid asphyxia. The lip is the best developed site for cellulitis, a very serious inflammatory disease that not only causes swelling of the lips, but may also lead to severe sepsis and even life-threatening conditions. The above situation should be seen immediately at the hospital and treated with antibiotics under the guidance of the doctor. Lip swelling caused by apical inflammation of the front teeth should be seen at the Department of Dentistry or the Department of Endodontics of a dental hospital for root canal treatment, and the lip swelling will recover after the tooth is cured. Some have formed abscesses that need to be incised and drained, along with anti-inflammatory treatment. After the swelling of the mouth we should look for the cause of the swelling of the mouth as soon as possible, after all, different causes correspond to different treatment methods, so that the swelling can be quickly reduced.