Your Health

Children's Fever

Note: This page provides basic information on fever but is not a substitute for professional medical advice. Talk to your doctor or go to a hospital emergency department if you have concerns about your child’s health.

What is a fever?

A fever is an abnormally high body temperature. Most of the time this is a normal response to infection. However, just because your child has a slight fever does not necessarily mean that he or she is seriously ill. (Generally, if your child feels well enough to do so, he or she can still go to school or child care.) Keep in mind that your child can also be sick and have a temperature that is normal or below normal.

What is normal body temperature?

Normal body temperature is 37°C (98.6°F) when measured orally, although there can be slight differences in temperature between children. Normal body temperature may even vary slightly - by 0.5°C to 1°C (1°F to 2°F) - depending on how and when it is measured. It is typically lower in the middle of the night.

A child may have a higher body temperature:

  • round mid-afternoon
  • in hot weather
  • during active play or exercise
  • when crying
  • while wearing warm clothing

How can I tell if my child has a fever?

You can do a quick check for fever by using your cheek to feel if your child’s forehead is hot. However, you should use a thermometer for an accurate temperature reading. If possible, avoid using mercury thermometers. If you must use one, handle it carefully so it does not break.

Taking your child’s temperature

There are several different ways to take a temperature — in the mouth, armpit, ear (using a special tympanic thermometer), or rectum. The following table describes these different methods and specifies the temperature reading that indicates a fever. Whatever method you use, always use a clean thermometer or one with a new disposable sanitary cover. If you use a digital thermometer, make sure your child keeps still while you hold the thermometer in place until it signals a reading. If you aren’t sure how to take your child’s temperature accurately, talk with your doctor or your Peoples pharmacist.

Different ways to take your child’s temperature

Method Use this method for… Steps Minimum
temperature indicating
a fever
Mouth Children 5 years and older 1. Make sure the child has not had hot or cold liquids for at least 5 minutes before taking the temperature.
2. Put the tip of the thermometer under the child’s tongue.
3. Close the child’s mouth.
Tell the child not to bite the thermometer.
Armpit* Children of any age 1. Put the tip of the thermometer close to the armpit, under the child’s arm.
2. Keep the child’s arm snug against his or her body.
38°C (100.4°F)
Ear Children
2 years and older
1. Use a tympanic thermometer and follow the thermometer instructions.
2. Use a clean probe tip for each reading.
3. Pull the ear back gently to straighten out the passage to the ear drum.
4. Insert the thermometer into the ear gently, sealing off the ear canal.
38°C (100.4°F)
Rectum Children of any age 1. Use petroleum jelly to lubricate the tip of the thermometer.
2. Insert the bulb end gently into the child’s rectum and hold it in place. Do not insert it further than 2.5 cm (1 in.).
38.5°C (101.3°F)

Children 3 months or younger:
38°C (100.4°F)

*Note: Armpit readings are generally not accurate. If the child is less than 2 years old, confirm a high armpit reading by taking a rectal temperature.

How can I treat a fever?

To treat a fever, follow these basic guidelines:

  • Give your child plenty of liquids.
  • Maintain a comfortable room temperature.
  • Dress your child in light cotton clothing. Keep bedclothes to a minimum.
  • Wet a sponge or cloth with lukewarm water and wipe your child’s face gently.
  • Do not use baths or alcohol rubs to cool down your child.
  • If your child is uncomfortable or the fever is high, use acetaminophen (People first brand, Tempra or Tylenol) or ibuprofen (People first brand, Motrin or Advil). Do not exceed recommended doses.

Important: Children and teenagers should not take ASA (Aspirin) or “baby” Aspirin when they have a fever. Giving ASA to children with fever has been linked to Reye’s syndrome, a serious disease.

Convulsions in young children

Children between about 6 months and 5 years old may have a febrile convulsion if their temperature rises quickly. This is not abnormal; about 4% to 5% of all children have at least one fever-related convulsion. Febrile convulsions generally last less than 5 minutes and are not harmful. The child’s face may turn blue and the arms and legs may shake uncontrollably. Even though these convulsions are likely the result of a febrile convulsion, just to be sure you should call your doctor immediately after the seizure stops (or after 5 minutes if the seizure continues) to rule out serious infection or other possible problems.

Does my child need to see a doctor?

If your child has a fever, consult with a doctor if you notice any of the following behaviours or symptoms:

  • lack of responsiveness, sleepiness, or lethargy
  • excessive fussiness or irritability
  • persistent coughing or wheezing
  • a rash
  • other signs of illness that concern you

The following table describes other circumstances in which you should seek medical help for your child.

Age of child Temperature Instructions
Babies up to 3 months old Any fever Call for help
immediately or visit the emergency department.
Babies up to 6 months old Any fever Call a doctor.
Any age Over 39°C (102°F) Call a doctor.
Any age Any fever for 24 hours Call a doctor.

Where can I find out more about fever?

For more information about fever:
• talk to your Peoples pharmacist
• read People First, a health magazine of practical information available free from your neighbourhood Peoples Drug Mart or Peoples Pharmacy

Other resources

Canadian Paediatric Society
Click “When your child is sick” and look for “Fever and temperature taking”.

Check your local phone book to find the nearest children’s hospital.

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