Children with blisters inside the lips should consider a variety of causes, such as hand, foot and mouth disease, trauma, allergies, vitamin B deficiency, etc., should be dealt with after clarifying the causes, common causes and treatment methods are as follows: 1, hand, foot and mouth disease: mostly occurs in children under 5 years of age, performance mouth pain, anorexia, low fever, hands, feet, mouth and other parts of the small herpes or small ulcers. Should promptly go to the hospital, pay attention to avoid cross-infection, give the baby good oral cleaning and care, trim the baby’s nails to prevent scratching the skin; 2, trauma: such as burns, stab wounds, misuse of corrosive food can lead to oral blistering. After scalding or accidental ingestion of corrosive food, you should immediately rinse your mouth with a lot of water, do not apply toothpaste, soy sauce, etc., so as not to cause wound contamination. Minor stab wounds caused by small blisters can be temporarily observed, if the wound is larger or bleeding more, should promptly seek medical attention; 3, allergies: can lead to oral mucosa blistering, should go to the hospital to do allergen examination, to clarify the cause, avoid contact with allergens again; 4, vitamin B deficiency: vitamin B deficiency can lead to oral mucosa blistering, usually should be intake of food containing vitamin B, such as asparagus, almonds, lean meat, eggs, chicken The food containing vitamin B, such as asparagus, almond, lean meat, egg, chicken, peanut, milk, animal liver, etc.