In the vast majority of cases, antipyretic drugs can be applied to children with an axillary temperature of 38.5°C. The criteria for the use of antipyretic drugs in children are defined on the basis of a large number of clinical practices. The reason for defining the criteria for taking antipyretic drugs for children is based on the analysis of a large number of clinical practices. Body temperature below 38.5 ℃ in the armpit, will not cause children to appear obvious headache, body soreness and weakness and other symptoms, for the children’s mental state and appetite for food has very little impact, coupled with moderate low fever, for children’s immune function is a benign stimulation. Therefore, based on the above points, children with axillary temperature of 38.5 ℃ only need to carry out physical cooling, drink plenty of warm water can be, without the routine application of antipyretic drugs. Children with axillary temperatures over 38.5 ℃ will cause headache and body aches, poor mental state and other symptoms, so this time to timely use acetaminophen and other antipyretic drugs for children.