Rotten lips mostly occur in the cold winter, due to the external environment of cold, dry, windy, or sun exposure, these external factors stimulate the lips, causing the phenomenon of rotten lips. In addition, many people do not like to eat vegetables, fruits, picky eating, partiality caused by the lack of vitamins and trace elements in the body, can also lead to the phenomenon of rotten mouth. Some people have the habit of licking the corners of their mouths with their tongues after the corners of their mouths have rotted, which will make the wounds on the corners of their mouths more and more serious. At the same time, if the human body immunity is low, it is easy to be infected by herpes simplex virus, causing herpetic stomatitis, resulting in blisters on the mouth, blisters broke leaving red, swollen, vesicles on the surface of the mucous membrane of the lips, which is also caused by rotting sides of the mouth causes.