Fever in Children & Teens

Fever is the body’s natural response to infection. An elevated body temperature can help the immune system kill off harmful germs. But fevers can be uncomfortable, and high fevers, particularly in children younger than age two, can cause dangerous complications, such as seizures.

What constitutes a high fever? Children’s body temperatures are generally higher and more variable than those of adults; also, a child’s age is taken into account in assessing a fever.

  • For a child up to a month old, a high fever is 100°F.
  • Up to three months: 101°F.
  • Up to two years: 103°F.
  • For older children: above 104°F.

Call your doctor promptly if your child has a high fever. Also call the doctor if any fever is accompanied by other symptoms like sore throat or listlessness, or if it persists for more than five days despite home treatment.

Children with fever should never be given aspirin (or other salicylates) because of the risk of Reye’s syndrome, a potentially fatal brain and liver disorder. Acetaminophen should be used instead, unless your doctor directs otherwise.

Taking A Child's Temperature

There are several ways to take a child’s temperature. An oral thermometer should generally not be used with children younger than age five, because they have trouble holding the thermometer properly under the tongue. Instead, use a rectal thermometer, which has a rounded bulb. The thermometer has to be inserted only about an inch into the rectum (you can use a lubricant on the tip) but should be kept in place for about two minutes to obtain a good reading.

Axillary thermometers that read the temperature under the armpit or temperature strips applied to the forehead are the least reliable gauges of body temperature.

Ear thermometers, which measure infrared energy from the eardrum, are fast (a few seconds) and accurate, though they are expensive (costing $60 or more) and generally are used by health professionals. (The tip of the device must be inserted precisely into the ear canal—otherwise you will get a lower temperature.) Some studies question their accuracy in children under three because kids that age squirm so much.

Publication Review By: the Editorial Staff at HealthCommunities.com

Published: 09 Aug 2010

Last Modified: 15 Sep 2015