[header] How to treat a fever [title] Let the fever run its course. [step] A fever itself is not necessarily unhealthy. It's not an illness; it's a physiological response to something else. 
Your body will often react to sickness or infection with a fever; it is a defensive response by your immune system as it tries to rid the body of pyrogens (fever-producing substances). [substeps] Acting too quickly to treat your fever can, counterintuitively, harm your body by undercutting one of its defensive measures.