Patients with inexplicable swollen lips have the following common clinical causes: a. Allergic patients who eat allergy-prone food or apply lipstick cause an allergic allergic reaction in the body, which results in obvious swelling of the lips and is accompanied by an increase in local skin temperature. At this time, patients need to stay away from allergens as soon as possible, and can reduce the allergic allergic reaction in the body by taking paracetamol and loratadine orally and applying ice to the swollen area, and most patients can gradually relieve the symptoms of swollen lips after 24-18 hours. Second, when the patient is accompanied by a mouth ulcer, the ulcer wound becomes seriously infected, which can also cause obvious swelling of the lips. Patients can take watermelon cream tablets, metronidazole tablets orally, and gargle with light salt water to control the bacterial infection in the mouth and promote faster healing of the ulcer wound, thus improving the symptoms of swollen lips.