Fever in babies: when to call the pediatrician
A fever is usually a sign that your child's body is fighting an infection. In young babies, though, even a mild fever needs a call to the doctor.
What counts as a fever
For babies and children, a temperature of 100.4°F (38°C) or higher is generally considered a fever.
Taking your baby's temperature
- Under 3 months: a rectal temperature with a digital thermometer is the most accurate.
- 3 months to 4 years: rectal, armpit (axillary) or a temporal artery (forehead) thermometer can be used. Armpit readings are less precise, so confirm a high or worrying reading.
- Over 4 years: oral readings work once your child can hold the thermometer under the tongue.
Don't use mercury thermometers. Ear thermometers are less reliable in young babies.
When to call right away
Call your pediatrician right away, day or night, if:
- Your baby is under 3 months and has a temperature of 100.4°F (38°C) or higher. Young babies can become seriously ill quickly, and they need to be checked even if they seem fine.
- Your child of any age has a fever and is hard to wake, unusually floppy or very irritable.
- Your child is having trouble breathing, has a stiff neck, a new rash that doesn't fade when pressed, or a seizure.
- Your child shows signs of dehydration: no wet diaper for 8 hours or more, a dry mouth, no tears, or a sunken soft spot on the head.
- The fever goes above 104°F (40°C) repeatedly, at any age.
What we mention
Call 911 for difficulty breathing, blue lips, a seizure that won't stop, or if your child can't be woken.
Also call if
- A fever lasts more than 24 hours in a child under 2, or more than 3 days in an older child.
- Your child has an ongoing medical condition.
- Your gut tells you something is wrong. You know your child best.
Comfort at home
For older babies who are otherwise well:
- Offer breast milk, formula or fluids often.
- Dress your child in light clothing, and keep the room comfortably cool. Avoid bundling.
- Let your child rest, and expect them to be clingy and eat less.
About fever medicine
Fever itself isn't harmful in most cases, and medicine is used mainly to help a child feel more comfortable. Talk with your pediatrician before giving any fever medicine to a baby under 6 months, and always ask for the right dose by weight. Never give aspirin to children.
Write it down
When you call, it helps to have the temperature reading and how you took it, when the fever started, how much your child is drinking, the number of wet diapers, and any other symptoms.
