Falling asleep with a high fever of 40 degrees can’t be left alone. High fever 40 degrees Celsius is more serious, if you fall asleep and do not care, do not promptly reduce the fever, the high temperature may cause generalized discomfort, and even symptoms such as convulsions of high fever. Therefore high fever 40 ℃ can not ignore. High fever 40 ℃ should be timely use of antipyretic drugs for treatment, can be taken orally, can also be plugged anally to reduce fever, commonly used antipyretic drugs are ibuprofen, acetaminophen and so on. In the use of medication at the same time, but also with physical cooling, such as warm water to wipe the body, cold towels with cold forehead, drink more warm water and so on. If the fever does not go down after the above treatments, you should also seek medical advice from your doctor to clarify the cause of the illness and then carry out targeted treatment.