Table of ContentsView AllTable of ContentsHow to TakeWhen to UseIdentifying a FeverWhen to Seek Help
Table of ContentsView All
View All
Table of Contents
How to Take
When to Use
Identifying a Fever
When to Seek Help
Learning how to use a rectal thermometer is essential if you have children younger than 4 years. Pediatricians recommend using a rectal thermometer because it produces the most accurate body temperature.
In children older than 3 months, you can also consider taking their temperature under the armpit or on their forehead. However, rectal temperature is preferred until your child can safely hold a thermometer under their tongue.
Steps to Take a Rectal Temperature
A rectal thermometer measures the body’s internal temperature after you insert it into the anus (the opening where bowel movements come out). It has a similar bulb-like shape as an oral thermometer but usually has a shorter and stubbier tip for easier insertion.
You’ll need adigital thermometerand a lubricant to take a rectal temperature. Digital thermometers are more accurate, take less time to get the temperature, and, most importantly, they’re not made of glass and don’t contain mercury.
You should not encounter resistance when inserting the thermometer. If it’s hard to insert, stop and withdraw the thermometer. Don’t try to insert a rectal thermometer if your child moves too much. Try to distract them, wait until they’re calm, or ask someone to help hold them.
Tip for Holding the Thermometer
Try this tip if you’re uncertain about how to tell when the rectal thermometer is inserted too far into the anus. Measure the metal tip on the end of the thermometer and use its length to visually gauge when you’ve inserted 1/2 to 1 inch.
When to Use a Rectal Thermometer
Pediatricians recommend using a rectal thermometer for children under 3 months. In fact, taking a rectal temperature is the preferred method until age 4.
After 3 months, you can check your child’s temperature in the armpit or forehead. If you prefer, you can use an ear thermometer after your child reaches 6 months.Keep in mind that armpit temperature readings are considered the least accurate.
After the age of 4, healthcare providers recommend taking an oral temperature if your child can hold the thermometer under their tongue.
How to Identify a Fever
You may wonder what’s considered a normal or high-temperature reading, especially if your child is an infant. The average normal body temperature is 98.6 F, but that number can vary depending on age, time of day, and how you take your child’s temperature.
For instance, rectal and ear temperatures are usually 0.5 F higher than oral temperature, while armpit and forehead temperatures are usually 0.5 F lower than oral temperature.
Despite variations, children have afeverwhen their rectal temperature is 100.4 F or higher.
When to Seek Help for a Fever
Babies Under 3 Months
You should also call your child’s healthcare provider if:
Children Older Than 3 Months
Babies and children older than 3 months with a rectal thermometer reading of up to 102.2 F should be monitored and can be treated with acetaminophen (Tylenol).However, consult your healthcare provider if your child is lethargic, irritable, or uncomfortable.
Call your healthcare provider if your child:
You should also seek help from your healthcare provider if your child has a fever together with any of the following:
Summary
Taking a rectal temperature is the best technique for babies younger than 3 months. However, pediatricians recommend rectal temperatures for all children younger than 4 years. Though you have options like taking the temperature in the armpit or forehead, rectal temperatures in young children are more accurate.
Even if you’re uncomfortable using a rectal thermometer, you can build your confidence and learn how to use a rectal thermometer following the six steps listed above.
5 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
American Academy of Pediatrics.How to take your child’s temperature.
Nemours KidsHealth.Taking Your Child’s Temperature.
American Academy of Pediatrics.Is a temperature ever normal?
MedlinePlus.Temperature measurement.
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