Children's Hospital Colorado

9 Fever Facts

A young girl wearing pink striped pajamas and holding a large stuffed teddy bear lies on a pink pillow while a parent feels her forehead.

Parents often worry and lose sleep when their child has a fever. In fact, fevers are harmless and often helpful. Below, Bart Schmitt, MD, a board-certified pediatrician at Children’s Hospital Colorado, gives you the facts about fever.

  1. Children can feel warm for many reasons. Examples are playing hard, crying, getting out of a warm bed or hot weather. They are “giving off heat.” Their skin temperature should return to normal in 10 to 20 minutes.
  2. About 80% of children who act sick and feel warm do have a fever. If you want to be sure, take the temperature. These are the criteria for fever using different types of thermometers:
    • Armpit temperature: 99 degrees Fahrenheit or higher
    • Oral (mouth) temperature: 100 degrees F or higher
    • Rectal, ear or forehead temperature: 100.4 degrees F or higher
  3. Fevers turn on the body’s immune system. They help the body fight infection. Normal fevers between 100 and 104 degrees F actually benefit sick children.
  4. Fevers don’t cause brain damage on their own. Only temperatures above 108 degrees F can cause brain damage.
  5. Fevers only need to be treated if they cause discomfort. Most fevers don’t cause any discomfort until they go above 102 degrees F.
  6. The brain has a thermostat. For that reason, most fevers from infection don’t go above 103 or 104 degrees F.
  7. Fevers often don’t come down to normal in response to fever medicine. But they will come back to normal in 2 or 3 days.
  8. If the fever is high, the cause may or may not be serious. If your child shows other symptoms, such as weakness or trouble drinking, the cause is more likely to be serious.
  9. How your child looks and feels is what’s important. The exact temperature is not. Keep in mind that fever is fighting off your child’s infection. Fever is one of the good guys.

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