For mosquito bites caused by blisters on the child’s legs can be applied to stop itching drugs, chickenpox caused by symptomatic treatment, for papular urticaria caused by symptomatic and anti-allergic treatment. 1. Mosquito bites: mosquito bites on children’s legs may lead to localized blisters, should be localized application of glycerite lotion and other anti-itching drugs. 2. chickenpox: mainly symptomatic treatment, itching skin can be oral loratadine oral solution antihistamines, if the blisters are not ruptured, can be coated with local glycerine lotion to stop the itching, if the blisters ruptured due to scratching or extrusion, can be coated with local antibiotics or iodophor skin disinfectant to prevent infection. Oral antiviral solution, oseltamivir phosphate granules and other drugs should be used for antiviral treatment. 3. Papular urticaria: mainly take oral loratadine oral solution and other anti-allergy drugs, or apply glycerine lotion and other itch-relieving topical drugs to treat the symptoms. In addition, hand-foot-mouth disease, burns, etc. can also lead to blisters on the child’s legs, should also be treated for the cause of the disease. When the child’s legs blisters, should go to the regular hospital timely consultation, clear cause, and under the guidance of the doctor for treatment.