39 ℃ fever overnight, is generally a more serious situation. Clinical body temperature of 39 ℃, known as hyperthermia, hyperthermia lasts a long time, easy to lead to the progress of the disease, but also can appear serious adverse consequences, easy to cause dehydration of the body, easy to lead to the function of various organs damage, but also may have a negative impact on the brain; for infants and young children can be induced convulsions. Therefore, the body temperature of 39 ℃, need to be given to reduce heat treatment, generally including physical cooling and drug cooling. Physical cooling: through the ice, warm water bath, etc., so that the liquid evaporation to absorb heat or heat conduction to absorb heat to achieve the effect of lowering body temperature. Drug cooling: you can give ibuprofen, acetaminophen and other oral medications, children can also be given diclofenac sodium anal plugs, through sweating to reduce fever and cool down the temperature. The use of antipyretic drugs need to comply with the doctor’s instructions, while actively seeking medical attention to find the primary cause of the disease, to avoid blindly taking on their own.