There is no fastest way to reduce fever. The ways to reduce fever in adults include physical cooling, oral medication, etc. Meanwhile, the cause of fever should be sought and treated according to the cause. 1. Physical cooling: when there is a low fever, body temperature does not exceed 38.5 degrees Celsius, you can use a warm towel to wipe the chest, back, bilateral armpits and other areas to dissipate heat. You can also use heat-reducing post, ice towel ice forehead and other ways to cool down. 2. Oral medication: When the body temperature is higher than 38.5 degrees Celsius, and physical cooling is still difficult to reduce fever, you can take some oral antipyretic drugs, such as acetaminophen tablets, ibuprofen extended-release capsules and so on, and it is recommended to use the drugs under the guidance of a doctor. When fever occurs, attention should be paid to replenish water to prevent dehydration due to high temperature and sweating, and bed rest and light diet should be paid attention to at the same time. If fever occurs, it is recommended to consult a doctor in time to find out the cause of fever and carry out targeted treatment to avoid delaying the condition. The use of drugs should be under the guidance of a doctor.