3-year-old baby with fever of 39.3 ℃ does not go down need to pay attention to whether there is timely use of antipyretic drugs, and whether the use of the appropriate dose, at the same time, need to clarify the cause of fever (such as intracranial infection, acute leukemia, etc.), and treatment. 3-year-old baby fever, body temperature of 39.3 ℃ has not subsided, need to pay attention to whether the timely use of antipyretic drugs (such as acetaminophen or ibuprofen), and according to the baby’s weight to determine whether the use of the dose is appropriate, such as the use of the right, the body temperature has not decreased, need to pay attention to whether the observation time is not enough. Usually after half an hour of using antipyretics, the temperature gradually decreases, and in some cases, the temperature may gradually decrease after 2 hours of use, during which time the spirit needs to be closely observed. At the same time, it is necessary to clarify the cause of fever, such as intracranial infection, high fever, temperature drop is not ideal, etc., need to actively treat the cause, such as bacterial infection caused by intracranial infection also need to actively use antimicrobial drugs (such as ceftriaxone) anti-infective treatment, need to use mannitol to reduce the cranial pressure, etc. If the acute leukemia, it is also necessary to use antifungal medication to reduce the cranial pressure. If acute leukemia, the above manifestations can also occur, may be accompanied by joint swelling and pain, bone marrow aspiration can assist in the diagnosis, need to actively consult the doctor, after the diagnosis is clear, under the guidance of the physician for radiotherapy or hematopoietic stem cell transplantation and other treatments. All of the above medications should be used under the guidance of a physician. When a baby has a high fever that does not go away, it is recommended that he or she be seen by a physician in a timely manner so that the physician can evaluate the cause of the fever and give him or her the appropriate treatment.