Fever's role in infections
What a fever means
A fever in infants and children can be scary, but it is common. It means your child's body is most likely reacting to an infection. Your child has a fever if their temperature is higher than 100.4 F by rectum. A rectal temperature is most accurate for children younger than 2 years old.
The degree of fever does not always show how bad an illness may be. Children often run a higher temperature than adults for the same illness.
More important than the fever is how your child looks and acts. Watch your child for signs of illness that include:
- appetite loss, abdominal pain or both
- headache
- weakness, fatigue (tiredness) or both
- thirst
- dry skin
- sore throat or swallowing problems
- breathing problems
- ear pain
- You should talk with your health care provider before giving fever-reducing medicine to a child younger than 2 months old.
- Use a rectal thermometer to get an accurate temperature reading for newborns to 1 year olds. Follow the package instructions.
- Don't give your child hot or cold liquids before taking their temperature by mouth.
When you should call your health care provider
Call your health care provider for an appointment if:
- your child is younger than 2 months old and has a temperature of at least 100.4 F by rectum
- your child is 2 to 3 months old and has a temperature of more than 101 F by rectum and has signs of illness
- your child has a temperature higher than 104 F by rectum
- your child's fever does not go down within 24 hours
- you gave your child over-the-counter fever medicine but the fever and signs of illness last for three days
- your child breaks out in a rash
- your child vomits
If your child appears ill and you are not comfortable with the way they look, call your health care provider right away, especially if your child has a fever (higher than 101.5 F), is unusually irritable, is not drinking enough liquids and has a lack of urine, has a stiff neck or is having trouble breathing. Same day appointments are available or you will be given other instructions for other medical care.
How to take your child's temperature
- After each use, wash the thermometer in clean, warm, soapy water. Wipe it with rubbing alcohol.
- Clear the thermometer of the previous reading by following the package instructions.
- Be with your child to make sure they stay still.
If you have a mercury thermometer, take it to a household hazardous waste collection facility. Do not use it and do not throw it in the garbage.
There are five ways you can take a temperature. Tell your health care provider knows which way you used.
Rectum
- Coat the tip of the rectal thermometer with a lubricant (such as Vaseline® or KY Jelly®).
- Gently insert the thermometer into your child's rectum. Do not go farther than the end of the silver tip, which is about 1/4 inch.
- Hold the thermometer in place for two to three minutes or until a digital thermometer beeps (usually 10 seconds).
Armpit (axillary)
- You may use a digital thermometer.
- Make sure your child's armpit is dry.
- Put the bulb under your child's arm, snug against their body.
- Make sure the thermometer stays in place for three to four minutes or until a digital thermometer beeps (usually 10 seconds).
Mouth (oral)
- Only use this method if your child understands that they must not bite the thermometer. This is usually around age 3.
- You may use a glass or digital thermometer.
- Put the bulb end of the thermometer under your child's tongue. Tell them to close their mouth but not to bite the thermometer.
- Keep it in place for two minutes or until a digital thermometer beeps (usually 10 seconds).
Ear
- Do not use on an infant younger than 6 months old.
- Follow the ear probe package directions carefully.
Temporal (forehead)
- Use as directed.
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