It is not recommended to wash your hair when you have a cold and fever, cold and fever is mainly due to the decline in immunity by viruses, bacteria and other pathogens, resulting in inflammation of the mucous membranes of the upper respiratory tract, the body’s immune response will be strong fluctuations in body temperature, or even lead to the symptoms of a persistent high temperature, the whole body’s blood vessels belong to the expansion of the state of the resistance to be relatively poor. If you wash your hair, it is likely to continue to expand the scalp blood vessels, causing generalized dryness and fever, which is not conducive to the reduction of body temperature. In addition, after washing your hair, you may get cold again because of the evaporation of water, and your immunity will continue to decline, which is unfavorable to the recovery of cold and flu. Therefore, when you have a cold and fever, you should drink more warm water and juice, pay attention to warmth to avoid getting cold, and it is not suitable to wash your hair for the time being.