Last Reviewed: April 2017
Serious warning signs
Take your baby to your doctor as soon as possible if he:
- Is less than 6 months old and has a temperature higher than 37.3oC (taken in the armpit).
- Has a fever for more than 72 hours.
- Seems too drowsy or sleepy, or isn't interested in normal activities.
- Has a poor skin colour or pallor.
- Is breathing faster than 40 breaths per minute.
- Is having difficulty breathing.
- Has a fever with a rash.
- Is drooling too much.
- Has a cough or wheezing that isn't going away.
If you're concerned at anytime about your baby's health, don't hesitate to take him to the doctor. You know your baby best.
Taking Care of Your Newborn
Fever and Illness
A normal body temperature for a newborn baby ranges from approximately 36.5oC to 37.5oC (when taken in the armpit).
- Means that your baby's body temperature is higher than normal.
- Is the body's normal response to fighting an infection.
- Is a symptom, not a disease.
Your baby's body temperature is important; however, how your baby looks and acts is more important than the number on the thermometer.
Vaccines, teething and fevers
Your baby might develop a low-grade fever after a vaccination, so it's important to follow your doctor's directions for fever-reducing medication after your baby is immunized.
Teething can cause a slight increase in body temperature, but not a fever.
Checking your baby's temperature
An axillary temperature is when the armpit (axilla) is used to check body temperature. The axillary method is the safest way to take your baby's temperature.
Only healthcare professionals should use a rectal thermometer to take a baby's temperature.
To check your baby's axillary temperature:
- Use a digital thermometer.
- Clean the thermometer with cool, soapy water and then rinse.
- Place the tip of the thermometer in the centre of your baby's armpit.
- Tuck and hold your baby's arm snugly against her body.
- Leave the thermometer in place for about 1 minute, until you hear the "beep."
- Remove the thermometer and read the temperature.
- Clean the thermometer with cool, soapy water, then rinse, dry and store.
Temperature-taking do's and don'ts
- Do use a digital electronic thermometer. This type of thermometer is a fast, accurate and safe way to check your baby's temperature.
- Do remove some of your baby's layers of clothing before taking his temperature for a more accurate reading.
- Don't use a mercury thermometer. Mercury is toxic: if the thermometer breaks, you and your baby risk being harmed by leaking mercury and broken glass.
- Don't use an ear thermometer. These type of thermometers are expensive, can be complicated to use, and can give inaccurate readings.
- Don't use fever strips: they don't give accurate readings.
- Don't use an oral thermometer until your child is at least 4 years old.
Fevers and seizures
A small percentage of children will have a seizure caused by only a fever (febrile seizure). They are most commonly found in children six months to six years. Febrile seizures can be frightening to parents and caregivers, but they usually don’t harm your child.
If the seizure lasts longer than three minutes, or if your baby is younger than six months call 911!
For more fever and febrile seizure information visit:
The Hospital for Sick Children's AboutKidsHealth