Fever is an extremely common symptom in pediatrics. Fever is a pathophysiological response of the organism to disease. During fever, metabolism is enhanced, a large amount of energy is consumed, non-significant water loss increases, and the body’s immunity is significantly enhanced at the beginning of the fever and decreases later. Short fever or low fever (below 38 degrees), the body does not have obvious discomfort. If the fever is prolonged or moderate (above 38 degrees), the body will have obvious discomfort, such as mental fatigue, general weakness, headache, body sickness, not thinking about eating and drinking, etc. Some children may also have febrile convulsions and other critical conditions. There are benign and malignant febrile convulsions. Benign febrile convulsions occur within the first 24 hours of fever, when the body temperature suddenly rises above 38.5 degrees; malignant febrile convulsions occur at any stage of fever, and some of them are epileptic or may develop into epilepsy. With sustained high fever, the body consumes a lot of energy and evaporates a lot of water, which can lead to life-threatening circulatory failure. The purpose of fever reduction is to relieve pain and discomfort, reduce energy expenditure and water loss, reduce the risk of febrile convulsions and reduce the risk of life-threatening circulatory collapse. The methods of fever reduction are divided into physical and pharmacological cooling. In winter, because of the low temperature, children are prone to chills, so it is recommended to use warm water baths to cool them down, and try not to use alcohol baths or cool water baths. In summer, the temperature is high, you can use cool water bath or alcohol bath or ice bag cold compress. Medication to cool down commonly taken drugs such as acetaminophen and ibuprofen. These two antipyretic drugs are safer and have little side effects. Because of the low fever below 38 degrees, the child has no obvious discomfort, generally not used as a cooling treatment. At the beginning of the fever, the child’s general condition is good, can be 38.5 degrees or more for cooling treatment. If the fever is long, lasts more than four hours, the child is poor in spirit, has obvious discomfort, or the child has a history of febrile convulsions, it is recommended that more than 38 degrees should be used for cooling treatment. If the child has a history of malignant convulsions, or has obvious headache, body pain, or joint pain, cooling treatment should also be given below 38 degrees. Most of the cooling drugs have pain-relieving effects, so they can be taken even if the child is not febrile and has obvious pain. A body temperature over 39.5 degrees has a greater negative impact on the child and can be combined with physical cooling and medication to lower the temperature. A body temperature above 40 degrees is extremely dangerous to the child, and adrenocorticotropic hormones can be used to reduce fever in a very positive way, along with anti-inflammatory, anti-toxic, anti-shock and auxiliary rib antipyretic. After taking antipyretic drugs, the antipyretic effect is often manifested one hour after taking the drug. There are often individual differences in the effect of antipyretic drugs in children. Some children are not satisfied with the effect of commonly used antipyretic drugs, because the half-life of commonly used antipyretic drugs in the body is one to two hours, so it is recommended that children can add half of the previous dose if they are not satisfied with the effect after one to two hours of medication. If the fever lasts for a long time, or the limbs are cold, often the effect of antipyretic is not satisfactory, while taking antipyretic drugs, it is recommended to drink more sugar and salt water to replenish energy and improve circulation, so that the effect of antipyretic will be better. The use of high doses of antipyretic drugs should be strictly prohibited in children, as they may cause damage to the liver, kidneys, stomach, nervous system, bone marrow, etc.