Taking your child's temperature

You kiss your child's forehead and feel a hint of heat. Could it be a fever? The back of your hand or your lips clue you in to a fever, but to know for sure, you'll reach for a thermometer.

How you'll take your child's temperature depends on your child's age - by mouth (oral), in the bottom (rectal), under the arm (axillary), or in the ear (otic):

For infants under the age of 2, opt for your baby's bottom or his/her armpit.

For tots between 2 and 5 years of age, your toddler's bottom will still get the most accurate reading, followed by his/her ear or armpit.

Children older than 5 are able to hold a thermometer in their mouth, and this method gives the most accurate reading. Checking temperature in the ear or armpit would be your next-best choices.

Your choice of thermometer will also depend on your child's age and how you've chosen to take their temperature:

Digital thermometers are quick, give an accurate result, and can be used to take oral, rectal, or under-the-arm temperature measurements.

Electronic ear thermometers are simple to use and easy to keep clean, but they are not as versatile, affordable, or accurate as a digital thermometer.

Plastic temperature strips are like a disposable bandage version of a thermometer you press against your child's forehead. While not very accurate, they might be a good option for stowing in the car or in your purse if you ever need a temperature-taking tool in a pinch.

Glass mercury thermometers are no longer a favoured choice, due to potential mercury exposure. Because mercury is an environmental toxin, check with a pharmacist or your doctor to get instructions for proper disposal of old mercury thermometers.

Normal temperatures depend on which method you use:

• 38°C (100.4°F) if measured rectally
• 37.5°C (99.5°F) if measured orally
• 37.3°C (99.1°F) or higher if measured under your child's arm
• 38°C (100.4°F) or higher if measured in your child's ear

No matter which method or thermometer you choose, it's important to take your child's temperature the right way to get the most accurate reading:

How to take a rectal temperature (for infants and children up to 5):

• Clean the thermometer with soap and cool water.
• Lubricate the tip with petroleum jelly.
• Lay your child on his/her back with knees bent. An infant can be on his/her belly across your lap or on a flat surface with your hand placed on your baby's lower back.
• Slip the thermometer about 2.5 cm (1 inch) into the rectum and hold in place.
• After 1 minute, remove the thermometer to read the temperature.
• Repeat the clean-up from step 1.

How to take an oral temperature (for children 5 years of age or older):

• Clean the thermometer with soap and cool water.
• Place the thermometer tip beneath your child's tongue.
• Instruct your child to keep his/her mouth closed while temperature is taken.
• After 1 minute, remove the thermometer to read the temperature.
• Repeat the clean-up from step 1.

Tips: Wait for a little while to take your child's temperature after he/she has had anything to eat or drink. Check for gum or candy in your child's mouth.

How to take your child's temperature under his/her arm (for children of all ages):

• Clean the thermometer with soap and cool water.
• Remove your child's shirt and slip the tip of the thermometer into the middle of your child's armpit.
• Tell your child to hold that arm tucked against his/her body while temperature is taken.
• After 1 minute, remove the thermometer to read the temperature.
• Repeat the clean-up from step 1.

How to take your child's temperature in his/her ear (for children 2 years of age or older):

• Check the instructions for your ear thermometer for details on measurement (how long to squeeze the button to get a reading, how far to insert the thermometer, etc.).
• Apply a clean tip before use.
• Tug your child's earlobe down and back to open the ear canal.
• Place the thermometer into your child's ear to the point that the ear canal is sealed off.
• Take the temperature measurement (instructions may vary).