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Fever in Children

This fact sheet answers frequently asked questions about fever in children.

Fever is an increase in body temperature above its normal temperature.

The basics

What is a fever?

A person’s normal body temperature changes during the day and is usually lowest in the morning and highest in the late afternoon. A normal temperature also depends on where you take it.

What causes a fever?

It is important to remember that, except in the case of heat stroke, fever itself is not an illness – only a symptom of one. Fevers help your body fight infection. Consider it a good sign that the body’s immune system is working and is trying to get rid of the infection. A fever does not mean that you need an antibiotic.

Will a fever cause harm?

A fever is not usually harmful. However, if your child is less than 3 months old and has a rectal temperature above 100.3° F you should call your baby’s health care provider right away. Even a slight fever can be a sign of a serious illness in an infant less then 3 months of age. With a high fever, some children may develop seizures, but this is rarely harmful.

How do I know if my child has a fever?

The only reliable way to know if your child has a fever is to use a thermometer. Testing a child’s forehead with your hand or lips is not accurate. If your child feels warm, take his/her temperature using a thermometer every 4 to 6 hours while awake.

Your child has a fever when the temperature is above: 

100.4º F measured rectally (bottom)

99.6º F measured orally

99.2º F measured in the axillary (under the arm) position

100.5º F measured in the ear


How can I help my child feel more comfortable?

There are some things that you can do to help your child feel better and bring down the fever slightly. 

  • Dress your child in light, loose clothes.  Do not bundle or swaddle the child
  • If your child is resting or sleeping, do not cover him/her with heavy blankets
  • Keep your child’s room cool
  • Make sure your child gets plenty of fluids
  • Make sure your child gets plenty of sleep and stays calm when awake     
  • A sponge bath in lukewarm water may make your child feel more comfortable. Use only lukewarm water, not cold. Do not give alcohol baths because the alcohol can absorb through the skin and cause health problems

Can I give my child medicine to bring down a fever?

It is important to remember that not all fevers need treatment. Never give a child or infant aspirin. You can give fever reducing medication such as acetaminophen or ibuprofen to children to bring down the body temperature. These medications will not treat the underlying cause of the fever.

  • Talk with your baby’s health care provider before giving any fever reducing medication to a child under three months of age
  • Do not give ibuprofen to a child under 6 months of age
  • Call your baby’s health care provider right away if your child is less than 3 months old and has a rectal temperature above 100.3° F
  • Call your child’s health care provider if your child is older than 3 months and has a fever greater than 102° F, if it lasts for more than 3 days, or if he/she is acting differently

When giving medicine, be sure to follow the instructions on the package to determine how much to give your child. If your child is taking medicine to reduce a fever, take their temperature just before the next dose is due. The dose for infant drops may seem small; but, it is very concentrated so never give more than it says on the box for your baby’s age and weight. Check with your child’s health care provider if you are not sure how much medicine to give your baby or child. For any liquid medicines, do not use a household teaspoon to administer, always use the medicine spoon, cup or dropper that comes with the medicine. Repeat doses as directed, but do not wake a sleeping child to give them medicine, unless directed to do so by your child’s health care provider.

When to call the doctor?

You can treat most fevers at home. Talk to your health care provider if you have questions about your child’s symptoms or fever management. You should get immediate medical care if your child:

  • Cannot hold down fluids
  • Has trouble breathing, even after nose suction
  • Turns blue
  • Has trouble swallowing or is drooling saliva
  • Has a seizure
  • Stiff neck or neck pain when bending head forward
  • Severe headache
  • Unusual rash
  • Eyes sensitive to light
  • “Acting sick” even after fever comes down
  • Any concerns or other unusual symptoms​
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