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How To Take A Temperature


What you need to know about taking a temperature:

  • There are several ways to take a temperature. The best ways are in the mouth, ear, underarm, or temporal (forehead). Digital electronic thermometers are the easiest and most accurate type of thermometer to use. Do not use mercury or glass thermometers.
  • A normal temperature is 98.6°F (37°C) but can range from 97.2°F to 99.9°F (36.2°C to 37.7°C). Body temperature varies during the day. It is usually lower in the morning and higher in the evening.
  • Your and your child's temperature can vary with activity or exercise. Wait at least 15 minutes after you or your child drink hot or cold liquids to take a temperature. Also wait 15 minutes after a warm bath. If your child is bundled, unwrap your child and wait 5 minutes before you take his or her temperature.

Types of thermometers:

Carefully read the instructions for each type of thermometer you use.

  • Digital thermometers are the most common and give the fastest, most accurate results. Digital thermometers can be used in the mouth, under the arm, or in the rectum. They are usually made of a flexible plastic with a sensor at the tip and a display window on the other end. If your thermometer comes with plastic covers or sleeves, use one each time you take a temperature. Throw the cover or sleeve away after each use.
  • Electronic ear thermometers are fast and easy to use. Ear thermometers may give you a low reading if there is extra wax in your ears or if it is not placed correctly in your ear.
  • Temporal artery thermometers are swiped over the forehead to behind the ear. This thermometer takes practice and may not be as accurate as a digital thermometer. You may need to check your or your child's temperature more than one time to get an accurate reading. Make sure the forehead is dry when you use this thermometer. Sweating can make the reading less accurate.
  • Pacifier thermometers should not be used in infants younger than 3 months old. Pacifier thermometers are less reliable than a rectal temperature. Your baby must hold the pacifier as still as possible to get an accurate reading.

How to use the thermometer:

Clean the thermometer with soap and warm water or rubbing alcohol before and after you use it. Do not submerge it in water.

  • To take an oral temperature , put the tip under your tongue as far as it can go. Close your lips gently around the thermometer. Do not bite the thermometer. Relax and breathe through your nose. Keep the thermometer under your tongue until it beeps. You can take your child's temperature in his mouth at 4 or 5 years old. Wait 20 to 30 minutes after you or your child finish eating or drinking to take an oral temperature.
  • To take an underarm temperature , put the tip in your or your child's armpit. Make sure the thermometer is touching skin and not clothes. Squeeze your arm against your body to hold the thermometer in place. Keep the thermometer in your armpit until it beeps.
  • To take a temporal temperature , push down on the button to turn it on. Swipe the thermometer from one temple to the other and behind the ear until it beeps.
  • To take an ear temperature , gently pull the adult ear up and back. When you take your child's temperature, pull the ear down and back. Put the thermometer tip into your ear. Do not use force or push hard. The thermometer tip should not touch the ear drum. Hold it until it beeps.
  • To take a rectal temperature , lubricate the tip of the thermometer with a small amount of petroleum jelly. Place your child face down across your lap or on a firm surface. Or, place your child face up with legs bent toward his or her chest. Gently insert the tip of the thermometer about ½ inch (1.25 cm) into the rectum. Never force the thermometer into the rectum. Stop if you feel any resistance. Hold it there until it beeps.

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The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.