Adults with fever can be physically cooled down through rehydration fluids, ice packs, and warm water baths. Physical hypothermia refers to a therapeutic operation to reduce the body temperature to normal with the help of ice packs, warm water wipes, ice caps, ice blankets, rehydration fluids, enemas, and other non-drug methods, and is mainly used in clinical practice to assist in the treatment of fever due to illness. Physical hypothermia is suitable for most adult patients because of its advantages of safety, reliability, convenience and rapidity, but it is not suitable for patients with large skin lesions to use surface physical hypothermia, or alcohol baths to lower the temperature, and patients with intestinal injuries should not use enemas or rehydration fluids through the mouth to reduce fever. If you have a fever, you need a specialist to clarify the cause of the disease and guide the treatment, do not blindly self-medication, so as not to cause adverse effects on the body.