Fever and children
Updated: Aug 4, 2022

Fever and children
Use a digital thermometer to check your child’s temperature. Don’t use a mercury thermometer. There are different kinds and uses of digital thermometers. They include:
· Rectal. For children younger than 3 years, a rectal temperature is the most accurate.
· Forehead (temporal). This works for children age 3 months and older. If a child under 3 months old has signs of illness, this can be used for a first pass. The provider may want to confirm with a rectal temperature.
· Ear (tympanic). Ear temperatures are accurate after 6 months of age, but not before.
· Armpit (axillary). This is the least reliable but may be used for a first pass to check a child of any age with signs of illness. The provider may want to confirm with a rectal temperature.
· Mouth (oral). Don’t use a thermometer in your child’s mouth until he or she is at least 4 years old.
Use the rectal thermometer with care. Follow the product maker’s directions for correct use. Insert it gently. Label it and make sure it’s not used in the mouth. It may pass on germs from the stool. If you don’t feel OK using a rectal thermometer, ask the healthcare provider what type to use instead. When you talk with any healthcare provider about your child’s fever, tell him or her which type you used.
Below are guidelines to know if your young child has a fever. Your child’s healthcare provider may give you different numbers for your child. Follow your provider’s specific instructions.
Fever readings for a baby under 3 months old:
· First, ask your child’s healthcare provider how you should take the temperature.
· Rectal or forehead: 100.4°F (38°C) or higher
· Armpit: 99°F (37.2°C) or higher
Fever readings for a child age 3 months to 36 months (3 years):
· Rectal, forehead, or ear: 102°F (38.9°C) or higher
· Armpit: 101°F (38.3°C) or higher
Call the healthcare provider in these cases:
· Repeated temperature of 104°F (40°C) or higher in a child of any age
· Fever of 100.4°F (38°C) or higher in baby younger than 3 months
· Fever that lasts more than 24 hours in a child under age 2
· Fever that lasts for 3 days in a child age 2 or older
Next Steps
Before you agree to the test or the procedure for your child make sure you know:
· The name of the test or procedure
· The reason your child is having the test or procedure
· What results to expect and what they mean
· The risks and benefits of the test or procedure
· When and where your child is to have the test or procedure
· Who will do the procedure and what that person’s qualifications are
· What would happen if your child did not have the test or procedure
· Any alternative tests or procedures to think about
· When and how will you get the results
· Who to call after the test or procedure if you have questions or your child has problems
· How much will you have to pay for the test or procedure