Fever is uncomfortable.  A child with a high fever will often seem irritable, lethargic, glassy eyed, listless, and otherwise "not himself".  The reason to treat fever is to relieve this distress.  Usually, once the fever comes down the child will seem happier, more alert, and more active.  This may be used as a "test": the child who's lethargy or irritability does not improve with a reduction of his temperature is likely to have a more serious underlying illness causing his fever and perhaps should be seen.  On the other hand, there may be no reason to treat even a high fever if your child seems happy, active, and alert.  Again, do not let fever be the overriding factor in you deciding how sick your child is.

The exception to the above is the infant less than 3 months old. A newborn's physiologic response to illness is immature, and unfortunately they do not always show the symptoms they are "supposed to" for a particular illness (i.e. they could have a pneumonia with no cough, meningitis with no stiff neck, etc.). Thus, fever in this age group (rectal temperature above 100.4°F) may be the only sign of a serious illness. For that reason, ALL infants less than 3 months with a fever should be examined.

A small percentage of children may be prone to convulsions with fever, or what is known as "Simple Febrile Seizures". This tendency runs in families, although a family history is not necessary for it to occur. The convulsions are related more to how quickly the temperature rises than to how high it actually is. They tend to occur between the ages of 6m and 6y - eventually being outgrown. They last less than 5 minutes, (usually less than one minute) and are characterized by loss of consciousness, stiffness, eyerolling, grunting noises, and shaking. They are followed by a 15-60 minute period of drowsiness. Simple febrile seizures are self limited and harmless - although they are one of the most frightening events a parent can witness. If this happens to you try to stay calm - make sure the child is breathing, loosen the clothing, and protect him from harm such as falls or bumps. This is not an emergency unless it fails to stop or breathing is impaired. Patients having febrile seizures for the first time will need to be seen to be sure that in fact that is what it was. Children experiencing repeat febrile seizures are seen only as their other symptoms may indicate. Fever control measures may be somewhat more important in children with a family history or known tendency towards this phenomenon.