When to worry about your baby's fever

My baby feels warm, but I don’t notice any other symptoms. Should I be worried? 

If you are concerned your baby has a fever, it is best to check their temperature. The most accurate way to take the temperature of a child under two is rectally. You don’t need anything fancy—just a simple electronic thermometer and a smear of petroleum jelly (Vaseline). Most thermometers will give you a reading in mere seconds, and your child likely won’t even notice the thermometer. Simply lift your child’s legs up, as if you are changing a diaper, and insert the Vaseline-covered thermometer into the rectum, only as far as the metal tip (less than a centimetre). A reading of 38 degrees Celsius (100.4 degrees Fahrenheit) or higher indicates a fever. Older children can have their temperature taken orally with the thermometer under the tongue, or in the armpit. In these areas, a fever is 37.5 degrees Celsius (99.5 degrees Fahrenheit) or higher.

If your baby is two months or younger with a confirmed fever, please head to your nearest emergency room. Babies this young are more at risk of dangerous bacterial infections and need to be examined and treated for fever ASAP. If your child is older and has a fever, consider giving some acetaminophen (15 milligrams per kilogram) or ibuprofen (10 milligrams per kilogram) and reassessing in 20 minutes to see how they’re doing. If they’re acting more themselves after the medicine, and are drinking and interacting well, you can continue to treat at home for two to three days. If your baby is lethargic, not drinking, not breathing normally or otherwise unwell, or if the fever persists longer than three days, see your doctor.

Read more: When should I take my child to the ER? Is there such thing as a teething fever?