A fever of 39°C in adolescents is considered high. This situation is generally more serious, sustained high fever easily lead to human body fatigue, aches and pains, mental depression, low appetite and so on. You can place an ice pack on the head to help dissipate the heat, as well as warm water to scrub the armpits, groin and other parts of the body rich in blood vessels. Medications can be injected with Zheng Chai Hu Drink to help reduce fever, as well as oral paracetamol or ibuprofen to reduce fever. Ensure that you drink enough water during the fever to help increase sweating. During the illness, try to rest in bed, do not wear too thick clothes to avoid affecting heat dissipation, reduce clothing and blankets appropriately, and open windows and ventilate the room diligently to keep the indoor air fresh, which will help the illness recover. If persistent high fever, oral medication can not be relieved, you need to go to the hospital in time to do blood tests, according to the results of the active anti-infection, fever treatment can be.