What fever level do I need to call for? Won’t fever cause my child to have a seizure or brain damage? Will my child’s fever just keep going up if I don’t do something? Should I alternate Tylenol and ibuprofen if my child’s fever continues?
If your child is < 90 days old, you must call immediately for temperature > or = 100.4 rectally. If your child is older than this, how your child feels is much more important than the height of the fever. If your child has fever of 104 but overall seems to feel okay, this is much less concerning than a child with fever of 101 who is lethargic. If your child's fever reaches 105.0, call us for advice on bringing it down and for assistance in determining whether your child needs to be evaluated before the morning. If your child has fever > 102.5, we should probably evaluate your child in the office the following day, even if symptoms seem mild.
In regard to seizures and brain damage, before the advent of the vaccines we benefit from now, high fever was often an indication of bacterial meningitis so it really was very scary for parents. It was the bacterial meningitis infection, not the fever itself, that caused seizures and brain damage. Nowadays, most fevers -- even high ones -- are secondary to viral illnesses that the body is able to fight off on its own. In fact, fever is one of our body's protective mechanisms for fighting infection, as many viruses and bacteria do not grow as well at higher temperatures. Because of this, some physicians advocate not treating fever at all! Here in the US, however, we typically recommend treating fever simply to help the child feel better.
There is a condition called “febrile seizures” that certain children have. These seizures (like all seizures) are scary to see, but they are harmless and do not cause any long-term damage. Only certain children have febrile seizures and there is no way to predict which child will and which won't. However, for children who do have febrile seizures, it is not the height of the fever that causes the seizure anyway, and interestingly anti-fever medications do not prevent febrile seizures.
Fever will not increase infinitely. Your child’s body will top out a fever at 105-106, unless something else is already seriously, seriously wrong. The higher the fever, the higher the risk of an underlying bacterial infection though, so higher fevers do warrant evaluation more frequently than lower fevers.
We do not recommend alternating Tylenol and ibuprofen. Studies have shown that alternating is not more effective than giving either medication alone, and it significantly increases the risk of medication error. Keep in mind that fever will probably only decrease 1.5-2 degrees after a dose of Tylenol or ibuprofen, so do not expect temperature to return completely to normal if your child's fever is high. Also keep in mind, that it takes 45-60min for either medication to take effect. If fever does not decrease all the way to normal or if fever recurs before it is time for the next dose of anti-fever medication, simply wait. Do not repeat Tylenol more frequently than every 4-6hrs or ibuprofen more frequently than every 6-8hrs.