We get many calls every day about this topic.  The most important things to know are:
(1)  Fever is your friend!  Pathogens like viruses can not live at high temperatures so this is the body’s response in order to fight off the illness.  Fever does a better job warding off the virus than antibiotics ever could!
(2)  Your child’s brain is not going to “fry” from a fever that is in response to illness.   Some viruses, like influenza, can even cause fevers up to 106 F.
(3)  We treat fever in order to make your child feel more comfortable.  The fever is going to run its course in spite of ibuprofen (Motrin/Advil) or acetaminophen (Tylenol). Giving either Motrin (after 6 months of age) every 6-8 hours or Tylenol every 4-6 hours is appropriate in order to make your child feel better.
(4)   We do not routinely recommend alternating Motrin and Tylenol.  This can get very confusing and you run the risk of overdosing your child on one or the other, which could cause liver or kidney toxicity.  Remember the point of these medications is for “comfort” and may not return your child’s temperature to “normal”.
(5) Do not wake your child to take their temperature or give them medicine for fever.  Sleep is important to help them fight their infection!