When to see a healthcare professional

A fever is a common sign of illness, but that's not necessarily a bad thing. In fact, fevers seem to play a key role in fighting infections. If your child is older than 6 months and is drinking plenty of fluids, sleeping well and continuing to play, there's usually no need to treat the fever.

If you want to give your child medicine to treat a fever, stick to acetaminophen (Tylenol, others) until age 6 months. However, for children younger than age 3 months, don't give acetaminophen until your baby has been seen by your healthcare team. Never give more acetaminophen than recommended on the label for your child. Be aware that some combination over-the-counter medicines might contain acetaminophen as an ingredient.

If your child is age 6 months or older, ibuprofen (Advil, Children's Motrin, others) is OK too. Read the label carefully for proper dosage. Don't use aspirin to treat a fever in anyone age 18 years or younger.

Your child has a fever if your child has:

• A rectal, ear or temporal artery temperature of 100.4 degrees Fahrenheit (38 degrees Celsius) or higher.
• An oral temperature of 100 degrees Fahrenheit (37.8 degrees Celsius) or higher.
• An armpit temperature of 99 degrees Fahrenheit (37.2 degrees Celsius) or higher.

Keep in mind that an armpit temperature might not be accurate. If you're in doubt about an armpit temperature reading, use another method to confirm the results.

In general, contact your child's care team if:

• Your child is younger than age 3 months and has a rectal temperature of 100.4 degrees Fahrenheit (38 degrees Celsius) or higher.
• Your child is age 3 to 6 months and has a temperature up to 101 degrees Fahrenheit (38.3 degrees Celsius) and seems unusually irritable, lethargic or uncomfortable, or has a temperature higher than this number.
• Your child is age 6 to 24 months and has a temperature higher than 101 degrees Fahrenheit (38.3 degrees Celsius) that lasts longer than one day but shows no other signs. If your child has other signs, such as a cold, cough or diarrhea, you might call your child's care team sooner based on the severity of the other signs.
• Your child with a fever has a febrile seizure for the first time.