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How to take a rectal temperature
A rectal thermometer is the most accurate way to take a temperature.
To take a rectal temperature:
- Apply a lubricant jelly or petroleum jelly, such as Vaseline, on the bulb of the thermometer so that you can insert it easily.
- Choose a quiet place so that the child won't be distracted or move around too much. If you are measuring the temperature of a baby or small child, you can:
- Place the child faceup with legs bent toward the chest with your hand on the back of the thighs or holding the feet as if you were changing a diaper.
- Place the child facedown on your lap or on a flat covered or padded surface, such as a bed.
- Gently insert the bulb end of the rectal thermometer about 0.6 in. (1.5 cm) to 1 in. (2.5 cm) into the anal canal. Don't force it into the rectum. Hold the thermometer in place with two fingers close to the anal opening (not near the end of the thermometer).
- Leave the thermometer in place for the required amount of time, usually a minute. Time yourself with a watch or clock. Some digital thermometers give a series of short beeps when the reading is done.
- Remove the thermometer and read it.
- Clean a digital thermometer with cool, soapy water, and rinse it off before putting it away. After a thermometer has been used to take a rectal temperature, do not use it to take an oral temperature.
Current as of: August 6, 2023
Author: Healthwise Staff
Clinical Review Board
All Healthwise education is reviewed by a team that includes physicians, nurses, advanced practitioners, registered dieticians, and other healthcare professionals.
