Blister refers to blisters in clinic, long blisters under lips may be related to herpes of mouth and lips, burns and other diseases, which need to be improved by general treatment, medication, surgery and other ways. 1. Oral and lip herpes: oral and lip herpes may cause blisters under the lips, patients should drink more water, light diet, can follow the doctor’s instructions to apply acyclovir, penciclovir and other drugs to help anti-virus, astringent, analgesic and other efficacy, can improve the local appearance of blisters. 2. Scalding: blisters under the lips may be caused by scalding, the patient should ensure that the wound is clean, you can use ice packs to ice the affected area, to alleviate the scalding situation. If the blisters are small, you can apply moist burn cream. If the blister is large, you should cooperate with the doctor to pick it, and then apply antibiotic drugs locally, such as erythromycin and mupirocin, to prevent infection. The causes of blisters under the lips are not one, it is recommended that patients go to a regular hospital to check, clear cause of the disease with the doctor standardized diagnosis and treatment.