Fever is the most common reason children visit a pediatrician. Although it is extremely common, it is a source of concern for many parents. In most cases, however, fever is harmless and need not be feared. Fever is a symptom, not a disease, and the fever itself is not harmful. It is much more important to know what is causing the fever and to appropriately treat its cause. The way the child looks and acts overall is far more important than how high the fever is.

Decription… What is Fever?

Fever is defined as an elevation in body temperature above 100.4°F (38°C). The body’s average temperature is 98.6°F (37°F), but it normally fluctuates during the day, within a normal range of 97°F and 100°F. Many people, including children, have a natural rise in body temperature in the evenings to 99°-100°F.

Exercise, hot weather, being dressed too warmly or with excessive clothing, or a hot bath can raise the body temperature up to 101.3°F (38.5°C). Warm foods and drinks can artificially elevate a temperature taken orally. If you suspect such an effect on your child’s temperature, wait half an hour and retake the child’s temperature again.

Fever helps the body to fight the infection (therefore it may be good to let the child have the fever as long as it is not making the child uncomfortable).


Fever is a symptom, not a disease. This is very important as you deal with your child’s fever. It is the body’s normal response to infections and plays a role in fighting them. Fever turns on the body’s immune system. It is usually a part of the way the body fights an infection, which is a good sign that the immune system is working to get rid of the infection.

The usual fevers 100°F to 104°F (37.8°C to 40°C) that all children get are not harmful. Most are caused by viral illnesses; some are caused by bacterial illnesses.

Teething does not cause fever. There are other causes of fever besides common childhood illnesses; however, these fevers will be unusual in nature (how long they last, etc.) and will not follow the pattern described here. When in doubt, call your Pediatrician or contact our office.

Expected Course

Most fevers from viral illnesses range between 101°F and 104°F (38.3°C to 40°C) and last for 2 to 3 days. In general, how high the fever is does not relate to the seriousness of the illness. How sick your child is and acts is far more important. Fever does not cause any permanent harm until it reaches 107°F (41.7°C). Fortunately, the brain’s thermostat will not let fever go high enough to be harmful, because it works to keep it below this level.

The fever will rise and fall during the course of the illness. Treating the fever with medication may lessen the fever, but the temperature may rise again when the medicine wears off, and this is to be expected. The fever will continue until the underlying cause is treated or resolves, and repeated doses of medication may be necessary.


Not all fevers need to be treated. If the child is uncomfortable (toddlers are often fussy or clingy and don’t sleep well), then treatment may make the child feel better and perhaps drink more fluid and sleep better. Remember, the fever is not a danger to your child, and it is helping to fight the infection. You should only treat the fever if your child is uncomfortable, which may be manifested as crankiness or fussiness in a toddler. You should never use aspirin to treat a fever in a child.

    1. Plenty of fluidsFever causes the body to lose more fluid through evaporation and sweating. Encourage plenty of fluids; popsicles, pedialyte, and other fun, tasty fluids can be given. Watch for signs of dehydration; make sure your child is making adequate urine.
    2. Comfortable clothingChills may occur as the fever rises, and sweating as the fever falls. In general, keep the room at a comfortable temperature and the child dressed comfortably, but not over bundled or overdressed. A blanket can be used when the child feels cold and then removed when sweating.
    3. AcetaminophenAcetaminophen can be given to children ages 2 months and above. It can be given every 4 to 6 hours. The dose to give depends on the child’s weight; see the dosing chart for details. Give the correct dosage for your child’s age. It can be expected to bring the temperature down a degree or two; it will not usually bring it down to normal.
    4. IbuprofenIbuprofen can be given to children ages 6 months and above. It is given every 6 to 8 hours as needed (it lasts a little longer than acetaminophen). Give the correct dosage for your child’s age. Both medications, as far as we know, are safe and effective. The dose to give depends on the child’s weight; see the dosing chart for details.
    5. Alternating acetaminophen and ibuprofenThis is a behavior now becoming very popular with many parents. If you are instructed by your physician to do this, follow these instructions:
      • Alternate both if the fever is over 104°F (40°C) and not responding to one medicine alone.
      • Give a fever medicine every 4 hours.
      • Only alternate medicines for 24 hours or less, and then return to a single product.
      • Call your pediatrician or contact our office, if your child is not improving.

Beware: Giving both medications may increase dosage errors, which can lead to an overdose.

    1. Sponge baths/lukewarm bathsThis is usually only necessary if the temperature is over 104°F (40°C). It may be a quick way to make a child more comfortable. If you are going to give a sponge or lukewarm bath to bring down the fever, keep the following in mind:
      • Give medication (acetaminophen or ibuprofen) at least 30 minutes before the bath, to reset the brain’s thermostat (as discussed above).
      • If you make the body colder than the brain thinks it should be, this will just make the child uncomfortable and cause shivering as the body tries to warm up again.
      • Be sure the water is not too cold. Use lukewarm water.
      • Never use rubbing alcohol or add rubbing alcohol to the water. This can cause a coma.

When to call the doctor

Immediately If:

      • Your child is less than 3 months old
      • The fever is over 105°F (40.6°C)
      • Your child develops a rash with the fever.
      • Your child looks or acts very sick.

Within 24 hours if:

    • Your child is 3-6 months old (unless the fever is due to vaccination).
    • The fever is between 104°F and 105°F (40°C to 40.6°C), especially if your child is less than 2 years old.
    • Your child has had a fever for more than 24 hours without an obvious cause or location of infection.
    • Your child has had a fever for more than 3 days.
    • The fever went away for more than 24 hours and then returned.
    • You have other concerns or questions.