Clinically, a high fever for 3-5 days can be harmful and dangerous to the human body, often leading to many complications, and what are the specific hazards of high fever in the following areas: 1. 2. If patients with high fever do not receive timely treatment and nutritional supplements, further aggravation of the disease will likely cause digestive system pathologies, such as nausea, vomiting and other symptoms, and may also lead to malnutrition. 3. High fever can also lead to pathologies in other systems, such as coronary heart disease, angina pectoris and other symptoms, and there may be kidney damage. The above analysis shows that high fever can also lead to lesions in other systems. Therefore, through the analysis of the above points, patients with high fever should actively search for the cause of the fever once it burns for 3-5 days, treat the symptoms, reduce the fever as soon as possible and avoid damage to the organs.