The itchy body of a 6-year-old baby with fever has to be considered to be related to the disease, mostly due to infectious allergic diseases, that is, both allergic and infectious symptoms, and the blood test shows an increase in white blood cells, which is due to infection-induced fever and allergy. In addition, the itching is caused by drug allergy after the baby takes fever-reducing medicine, such as taking some western medicine to reduce fever, common drugs such as acetaminophen and ibuprofen suspension, to rule out whether the itching is caused by drug allergy. 6-year-old babies are also prone to some rash diseases, such as rubella, measles and other diseases, there will be a fever first and then a rash and accompanied by itching symptoms. Itchy symptoms, according to the specific cause of the baby’s disease and accompanying symptoms can be identified.