The blisters around the lips are usually considered to be caused by local skin allergic reactions and herpes simplex. 1. Allergic reaction: small blisters around the lips may be due to allergic reactions caused by the consumption of allergenic food, drugs, etc., usually manifested as swollen lips, blisters around the lips and accompanied by pain, itching and other symptoms. 2. Herpes simplex: Herpes simplex virus infection can also cause clusters of small blisters around the lips, when the patient is overworked or suffers from chronic underlying diseases and other factors that lead to low immunity, the latent herpes simplex virus in the body is easy to be activated and the onset of the disease. There are many other causes of blisters around the lips, it is recommended to go to the hospital in a timely manner, after clarifying the cause of the disease to carry out targeted treatment, in order to reduce the adverse effects of the disease.