There are many reasons for blistering under the lips: first, it may be related to the daily diet, such as like to eat spicy and stimulating food, these foods eat too much may stimulate the mucous membrane of the lips, too spicy things eat too much will cause dehydration, fire, it will be easy to make the lips blister. Secondly, lip blisters may be caused by herpes virus infection, human beings at times when the immunity and resistance is lowered, it is easy to be infected by herpes virus. The phenomenon of herpes on the lips need to eat a light diet, pay attention to the combination of work and rest, when appropriate, you can take anti-virus oral solution.