Fever in Children and Teens

Fever in Children

Fevers are very common in children. They are usually a sign that the body is trying to fight an infection.

The normal temperature of the body is 98.6F, or 37C. Your child's temperature may vary during the day and may increase a little when he's bundled up or very active. Generally, doctors say that there is a fever when the temperature is greater than or equal to 100.4F, or 38C.

Use a digital thermometer to take your child's temperature; never use a glass mercury thermometer. Most children aged three years and older can hold a thermometer under their tongue. If your child is younger than that, or you're having difficulty with the oral method, talk to your doctor about the best way to take his temperature.

Use this guide if your child is over a year old. If he or she is younger than 12 months of age, visit our Fever in Infants guide.

The guide is designed to help you understand what may be the cause of your child's fever and the actions you should consider. Remember -- this guide is not meant to take the place of a call to or visit with your doctor. If your child has a chronic medical problem, such as sickle cell anemia, or is being treated for cancer or any other serious disease, you should absolutely call the doctor rather than using this guide.

Click here to begin.

While most fevers are not a sign of a serious infection, sometimes they can be.

Is any of the following happening with your child?

  • His neck is stiff.

  • He has a very bad headache.

  • Light bothers his eyes.

  • He is so sleepy it's hard to arouse him, or is very weak.

  • He seems confused.

  • He has dark red spots on his skin that don't get paler when you press on them.

  • He is breathing very quickly or having trouble breathing.

  • He is drooling a lot or won't drink.

  • His skin color is very pale or bluish.

  • He has a severe stomachache or other severe pain.

  • He is having shaking chills.

  • He is having repetitive jerking movements of his arms or legs and doesn't seem conscious during them.

Yes, one or more of these describe my child.

No, none of these describe my child.

The absence of any of the above symptoms makes a serious infection less likely.

Let's ask a few questions to see if we can figure out what's causing your child's fever.

Does your child have a cough, runny nose, or sore throat?

Yes, my child has a cough, runny nose, or sore throat.

No, my child does not have these symptoms.

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