In extreme weather, the temperature of the body is not constant because the weather is not uniformly warm or cold. What causes high and low body temperature? There are many causes of fever, including upper gastrointestinal tract infections, gastroenteritis, tonsillitis, pneumonia, etc. All of these can cause fever, and there are no specific medications available. Fever from viral infections will go down on its own by a certain time, so do not use medication blindly because of fever. The fever is often caused by respiratory tract infections, which often require fever-reducing or inflammatory medication. Pay attention to maintenance, don’t strain and get cold, and drink more water. After infection, it is seen in acute infectious diseases. A few patients in the late pregnancy still have a low fever that lasts for several weeks and is related to the fact that the function of the thermoregulatory center has not yet recovered. After streptococcal infection, after the respiratory tract infection, sustainability of hypothermia, increased anti-O titers in blood tests, accelerated sedimentation, rapid relief of symptoms after treatment with penicillin, salicylic acid, etc. Organic hypothermia, such as tuberculosis hypothermia, chronic focal infections, such as hyperthyroidism, connective tissue, tumors, leukemia, etc. The above is the explanation for the sudden high and low body temperature, part of which is physiological and, of course, part of which is pathological. In daily life there should be better habits and good habits to avoid this problem.