The hypothalamus in the brain, which is the body's heat regulating mechanism is affected by the pyrogens, or the white blood cells that are produced to fight the infection. So, in effect, we can say that the fever is what is fighting the infection. That is why it is not good to try to bring down a fever too much or too fast. A temperature of 100 to 101 degrees Farenheit is good for the body because it shows that the body is fighting the infection. However, if a fever goes too high, measures must be taken to bring the fever down a bit.
Antipyretics are medications that lower fever, such as tylenol, aspirin and so on.
Never give a child aspirin products if it is believed they have chicken pox or the flu. This could lead to a condition called Reye's Syndrome that is potentially fatal. When a fever is 104 or 105 degrees this is very high. Above 105 degrees, damage can occur in the nervous system. Also, seizures can occur above 102 degrees in some people, usually children.