Fever is the most common symptom we encounter in clinical practice, and almost everyone has fever in their lifetime. When you have a fever, you may feel weak, lose your appetite, lose interest, etc. We often encounter patients with fever who begin with the phrase “Doctor, please help me to reduce my fever. In clinical practice, we feel that not only patients have many misconceptions about fever, but also some clinicians have many problems with the management of febrile patients. We often encounter examples of patients with fever being given antibiotics, antivirals, proprietary Chinese medicines, hormones, and antipyretic drugs all at once, and this kind of medication without identifying the cause is sometimes not only ineffective, but may also cause serious allergic reactions and the spread of the disease. Fever is one of the most common clinical symptoms, it is not an individual disease, but only an external manifestation of many diseases. There are a hundred or so common causes of fever, and 400 or 500 slightly more common ones. There are many diseases that cause fever that I have never heard of as a specialist, and a single book, Practical Infectious Diseases, is over a thousand pages long, and this book lists only a fraction of the infectious diseases that can cause fever, while there are many more non-infectious diseases that can cause fever than are listed in this book. Therefore, to find the disease behind the fever is not a very simple matter, the doctor needs to conduct a comprehensive consultation, physical examination, and sometimes many auxiliary tests, blood tests, radiographs, etc. Through a comprehensive analysis, the cause of the disease can be found, and the cause can be removed before the fever is cured. Many people don’t understand how you can take so much trouble with a fever, and the first thing many patients and their families say when they come to the clinic is “Doctor, he/I have a terrible fever, hurry up and give him/me a fever. In many people’s opinion, it does not seem to be important to diagnose the disease clearly, as long as the fever has gone down, it seems to be cured, in fact, sometimes the fever can be counterproductive. On the Internet, we often encounter pediatricians complaining that if they don’t give fever reduction or if the fever doesn’t go down in half an hour with medication, some parents directly beat the doctor. Drug abuse can lead to delays and aggravation of the disease, as well as unnecessary side effects, such as allergies, such as antibiotic resistance, etc. For fever, finding the cause and treating the cause is the key, fever reduction is only a superficial effort to treat the symptoms but not the root cause, and it may also bring serious danger, so there is no need to rush to reduce fever. First of all, let’s talk about the etiology of acute fever. Most fevers in a short period of time are caused by infections of various pathogens, including viruses, bacteria, mycoplasma, rickettsia and so on, with viruses being the most common. The common cold is an acute infection of the upper respiratory tract caused by one or more viruses such as rhinovirus, paramyxovirus, etc. There is generally fever, sore throat, stuffy nose and runny nose. Fever is generally mild, low to moderate fever is the main symptom, a few people can be high fever, systemic symptoms are relatively light, blood test white blood cells are not high. Neutral ratio is basically normal, biochemical indicators are not special, chest X-ray no obvious abnormalities, the general natural course of about 7 days, the treatment principle is a light diet, drink more water, more rest, fever can be given warm water baths and other physical cooling is the main, high fever persistently does not subside can be given acetaminophen, ibuprofen and other appropriate antipyretic. The common cold does not require the use of antibiotics (also known as “anti-inflammatory drugs”), nor does it require antiviral treatment, nor does it require Chinese medicine injections such as febrifuge, phlegm fever, Yanshuning. If the secondary bacterial infection, such as coughing yellow sputum, chest X-ray found to have pneumonia, then you need to use antibiotics, under the guidance of a specialist in the use of antibiotics, do not abuse, the course of treatment is about 7-1 routine non-specific, can have liver and kidney function damage, early albumin low can be used as a reference indicator, early diagnosis of doxycycline treatment is preferred, tetracyclines and azithromycin can be used. Some patients require sexual heart valve replacement surgery. Autoimmune diseases leading to fever include lupus, vasculitis, adult Still’s disease, etc., which require specialist diagnosis. Among other diseases, the most common chronic fever is drug fever, and the most common drugs that cause drug fever are antibiotics, anti-tuberculosis drugs, and proprietary Chinese medicines, etc. It is always right not to take drugs indiscriminately. For fever, finding the reason behind the fever is the key. But clinically sometimes patients do burn very uncomfortable, need to reduce fever when how to deal with non- or antipyretic drugs are ineffective to continue ultra-high fever can be used to cool down the temperature blanket cooling machine and other cooling. For the patient, to actively cooperate with the doctor to identify the cause of the fever, do not rush to ask the doctor to reduce fever; for the doctor, to explain clearly to the patient what the fever is all about, to find out the cause of the cause of treatment is the key, do not abuse antibiotics and hormones. Before clarifying the cause, the principles of fever reduction are summarized in one sentence: physical cooling is the main, cautious use of antipyretic drugs, hormone antipyretic is prohibited.