Health & Info

When and how do you treat a fever?

Understanding Fever

What is considered "a fever"?

You child has a fever if any of the following apply:

Method of Taking Temperature Temperature
Rectal temperature over 100.4°F (38.0°C)
Oral temperature over 99.5°F (37.5°C)
Armpit (axillary) temperature over 99.0°F (37.2°C)
Ear(tympanic) temperature over 100.4°F (38.0°C) 
if thermometer is set in the rectal mode OR
over 99.5°F (37.5°C) 
if thermometer is set in the oral mode
Pacifier temperature over 99.5°F (37.5°C) 
Note: This method is not accurate in general except for newer digital Thermometers. 
This mode is okay for screening if your childis over three months old.

You may also know your child has a fever because he feels hot to the touch. This method of determining whether a child has a fever is more accurate than we used to think; however, if you're going to call your child's doctor about a fever, actually take his temperature using one of the methods above.

What is the body's normal temperature

The body's average temperature when it is measured orally is 98.6°F (37°C), but it normally fluctuates during the day. Mild elevation (100.4° to 101.3°F or 38° to 38.5°C) can be caused by exercise, excessive clothing, a hot bath, or hot weather. Warm food or drink can also raise the oral temperature. If you child, take his temperature again in one-half hour.



What causes a fever?

Fever is a sign, not a disease. Fever is the body's normal response to infections and plays a role in fighting them. Fever turns on the body's immune system. The usualfevers (100° to 104°F or 37.8° 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.


Expected Course

What can I expect to happen with fever?

Most fevers with viral illnesses range between 101° and 104° F(38.3° to 40.4°C), and last for two to three days. In general, the height of the fever doesn't relate to the seriousness of the illness. How sick your child acts is what counts.





Home Care

How do I treat a fever?

Treat all fevers with extra fluids and less clothing. Encourage your child to drink extra fluids, but do not force him to drink. Popsicles and iced drinks are helpful. Body fluids are lost during fevers because of sweating. Clothing should be kept to a minimum because most heat is lost through the skin. Do not bundle up your child; it will cause a higher fever. During the time your child feels cold or is shivering (the chills), give him a light blanket.


Should I give my child medicine to reduce a fever?

Remember that fever is helping your child fight the infection. Use drugs if your child is uncomfortable and the fever is over 102°F(39°C). Children older than two months of age can be given acetaminophen for reducing fever. Give the correct dosage for your child's age every four to six hours, but no more often. Ibuprofen products are also now available without a prescription. If you use ibuprofen products, give the correct dosage for your child's weight every six to eight hours as needed.


Can I give aspirin?

NO. The American Academy of Pediatrics has recommended that children not take aspirin if they have the chickenpox or influenza (any cold, cough or sore throat symptoms). This recommendation is based on several studies that have linked aspirin to Reye's syndrome, a sever illness.


How much medicine do I give my child?

It is very important to follow the correct dosage for your child's weight. The following chars give the correct dosages for acetaminophen and ibuprofen.

Caution: The dropper that comes with one product should not be used with other brands.


How do acetaminophen and ibuprofen compare?

Acetaminophen and ibuprofen are similar in their abilities to lower fever, and their safety records are similar. One advantage that ibuprofen has over acetaminophen is a longer-lasting effect (six to eight hours instead of four to six hours). However, acetaminophen is still the drug of choice for controlling fever in most conditions. Children with special problems requiring a longer period of fever control may do better with ibuprofen.



Acetaminophen is safe and effective when used properly. To avoid giving your child too much acetaminophen:

  • Be sure you aren't giving your child more than one medicine containing acetaminophen. Many aver-the-counter cold and cough medicines contain acetaminophen Look carefully at the list of ingredients.
  • If your child is taking acetaminophen, be sure to tell the pharmacist when getting a new prescription for your child.
  • Don't substitute adult preparations of acetaminophen for pediatric preparations.

How will these medicines affect the fever?

Two hours after they are given, these medicines will reduce the fever 20 to 30F (1° to 1.5°C). Medicines do not bring the temperature down to normal unless the temperature was not very elevated before the medicine was given. Repeated dosages of the fever will be necessary because the fever will go up and down until the illness runs its course. If your child is sleeping, don't awaken him for medicines.

How do I take my child's temperature?

Obtaining an accurate measurement of your child's temperature requires some practice. The steps below summarize how to take your child's temperature using a glass (with mercury) thermometer. However, if you have questions about this procedure, ask your doctor or nurse to show you how it's done and then to watch you doing the same.


Step One: Preparing the thermometer

Shake a glass thermometer until the mercury line is below 98.6°F(37°C).


Step Two: Deciding where to take the temperature

Rectal temperatures are the most accurate. Oral or eardrum temperatures are also accurate if done properly. Armpit (axillary) temperatures are the least accurate but are better than no measurement. For a child younger than five years old, a rectal temperature is preferred. Armpit (axillary) temperature is adequate for screening if it is taken correctly. If your infant is less than 90 days old (3 months old) and armpit (axillary) temperature is over 99.0°F (37.2°C), check it by taking the rectal temperature. A rectal temperature is needed for young infants because, if they have a true fever, they need to be evaluated immediately. For a child 7 years old or older, take the temperature by month (orally).


Step Three: Taking the thermometer

Rectal temperature - 2 minutes

  • Have your child lie stomach down on your lap.
  • Before you insert the thermometer, apply some petroleum jelly to the end of the thermometer and to the opening of the anus.
  • Insert the thermometer into the rectum about one inch. During the first six months of life, gently insert the rectal thermometer 1/4 to 1/2 inch (inserting until the silver tip disappears is about 1/2 inch). Never try to force it past any resistance. (Reason: it could cause perforation of the bowel.)
  • Hold your child still while the thermometer is in.
  • Leave the thermometer in your child's rectum for two minutes.


Armpit (axillary) temperature - 4 minutes

  • Place the tip of the thermometer in your child's armpit. Make sure the armpit is dry.
  • Close the armpit by holding the elbow against the chest for four or five minutes. You may miss detecting a fever if the thermometer is removed before four minutes.
  • If you're uncertain about the result, check it with a rectal temperature.


Oral (by mouth) temperature - 3 minutes

  • Be sure your child has not had a cold or hot drink within the last 30 minutes.
  • Place the tip of the thermometer under one side of the tongue and toward the back. An accurate temperature depends on proper placement. Ask your doctor or nurse to show you where it should go.
  • Have your child hold it in place with the lips and fingers (not the teeth) and breathe through the nose, keeping the mouth closed.
  • Leave it inside for three minutes.
  • If your child can't keep his or her mouth closed because of nose blockage, suction out the nose.


Step Four: Reading the thermometer

Find where the mercury line ends by rotating the thermometer until you can see the mercury.


Are digital thermometers a good investment?

Yes. Digital thermometers record temperatures with a heat sensor and run on a button battery. They measure quickly, usually in less than 30 seconds. The temperature is displayed in numbers on a small screen. The same thermometer can be used to take both rectal and oral temperatures. They cost about $10.


Should I sponge my child?

Sponging is usually not necessary to reduce fever. Never sponge your child without giving him or her acetaminophen first. Sponge immediately only in emergencies such as heatstroke, delirium, a seizure from fever, or any fever over 106°F (41.1°C). In other cases, sponge your child only if the fever is over 104°F (40°C), the fever stays that high when you take the temperature again 30 minutes after your child has taken acetaminophen or ibuprofen, and your child is uncomfortable. Until acetaminophen has taken effect (by resetting the body's thermostat to a lower level), sponging will just cause shivering, which is the body's attempt to raise the temperature.

If you do sponge your child, sponge him in lukewarm water (85° to 90°F or 29° to 32°C). (Use slightly cooler water for emergencies.) Sponging works much faster than immersing, so sit your child in two inches of water and keep wetting the skin surface. Cooling comes from evaporation of the water. If your child shivers, raise the water temperature or wait for the acetaminophen to take effect. Don't expect to get the temperature below 101°0F (38.3°C). Don't add rubbing alcohol to the water, it can be breathed in and cause a coma.