Contact thermometers

A common type of contact thermometer is a digital electronic thermometer. It has a sensor that reacts to body heat and sends a signal that's read as a temperature on a digital display.

Contact thermometers may be used in the mouth, armpit or rectum. Or they may be used on the forehead.

Temperatures can be slightly different depending on where you take them on the body. There's no exact way to add or subtract a degree to make them match when temperatures are taken from different parts of the body. For this reason, it's best to compare readings taken the same way each time.

While temperatures from the rectum are the most accurate, rectal thermometers are invasive. They typically are used by healthcare professionals to check the temperature of infants when there are health concerns.

Healthcare professionals also may have parents or caregivers check rectal temperatures for infants if there is concern that they may have a fever. Rectal thermometers can be difficult or uncomfortable for some people, or in some situations. Oral thermometers are used more often, as they provide similar accuracy and are less invasive.

Pros of contact thermometers:

• Most digital contact thermometers can record temperatures very quickly.
• A digital contact thermometer is appropriate for any age, from newborns to adults.

Cons of contact thermometers:

• You need to wait 15 minutes after eating or drinking to take an oral temperature. This is because the temperature of your food or drink might affect the thermometer reading.
• Parents or caregivers may be uncomfortable or worry about a child's discomfort when taking a rectal temperature.
• Contact thermometers have to be cleaned very well after each use. They should be cleaned after each user and each use to limit the spread of germs. If you plan to use a contact thermometer to take both oral and rectal temperatures, don't use the same thermometer in both places. Get two thermometers. Label one for oral use and one for rectal use.