Checking your body temperature is one of the first steps you should take if you or someone you care for becomes ill. There are different types of thermometers that measure body temperature in the skin, mouth, or ear. However, research shows that a rectal thermometer can provide the most accurate temperature measurement, especially for babies.
What is a rectal thermometer?
A rectal thermometer is a thermometer that is inserted into the rectum to check your core body temperature. It is bulbous in shape similar to that of an oral thermometer, but generally has a shorter, stiffer tip to facilitate insertion into the rectum.
Pediatricians recommend them for babies younger than 3 months because they are generally more reliable and accurate than other thermometers. For example, the temperature measured with an oral thermometer can be easily influenced by drinking hot or cold beverages, while the ambient temperature can affect the reading of a skin thermometer.
Because rectal thermometers measure core temperature, they are less affected by these factors, resulting in more accurate readings.
Also, other types of thermometers can be uncomfortable for the baby and difficult to use. Measuring the temperature of the armpit (axial temperature) takes several minutes, which can be difficult for a baby. Also, babies and even some older adults cannot hold an oral thermometer under their tongue long enough to measure their temperature.
While temporal (forehead) artery thermometers are not as accurate as rectal thermometers, they are helpful for babies who cannot stay in place while taking rectal temperatures.
Steps to take a rectal temperature
To measure your rectal temperature, you need a digital thermometer and lubricant.
Follow these steps:
- Apply petroleum jelly or a water soluble lubricant (such as KY-Jelly or Surgilube) to the end of the thermometer.
- Lay the baby on his stomach and spread the buttocks to the sides or lay him on his back with his knees bent.
- Insert the end of the thermometer into the anal canal no more than 1 inch.
- Keep the thermometer in place until it beeps or for at least one minute.
- Remove the thermometer and read the result.
- Disinfect the thermometer with alcohol or an alcohol-based tissue.
Read a rectal thermometer
You may wonder what is normal or a high temperature, especially if your child is still a baby. Average normal body temperature is 98.8 degrees Fahrenheit, but this number can vary depending on how body temperature is measured.
For example, rectal and ear temperatures are typically 0.5 F higher than oral temperatures, while underarm and forehead temperatures are typically 0.5 F lower than oral temperatures.
There is no universal standard regarding normal body temperature in different age groups. Temperatures are generally considered 100.4 F or higher. if your body temperature is too low ( hypothermia ) 95 F or less.
However, certain age groups may require immediate medical attention to determine specific temperature values.
Babies up to 3 months
If your baby is less than 3 months old and has a temperature of 100.4 F or higher, call your doctor or go to the emergency room. If your baby also has trouble breathing, crying uncontrollably, a stiff neck, or seizures, go to the emergency room right away or call 911 . This could be an underlying problem, such as meningitis , that requires immediate medical attention.
If your child has a rectal temperature of 97.7 F or below, you should call your doctor to see if a hospital visit is necessary.
You should also call your child's healthcare provider if:
- The fever goes away but comes back.
- Your child will not be more alert or comfortable after the fever subsides.
- They have fevers that come and go for a week or more.
- Your fever lasts more than 48 hours.
Children older than 3 months (and adults)
Infants and children older than 3 months of age with a rectal thermometer reading up to 102.2 F should be monitored and can be treated with over-the-counter fever medications such as acetaminophen (Tylenol). Be sure to read and follow the dosing instructions for the product.
Babies 3 to 12 months of age with a rectal temperature reading of 95 F or lower or a fever of 102.2 F or higher should be evaluated by a doctor.
If a child has a temperature of 104 F or higher or a temperature of 100.4 F or higher with symptoms like shortness of breath, stiff neck, loss of consciousness, and seizures, take them to the emergency room right away.
If you are an adult and have a temperature below 95 F or a temperature above 104 F, you should see your doctor. You should seek immediate medical attention if you have a fever over 104 F with symptoms such as:
- Loss of consciousness
- Stiff neck muscles
- Difficulty breathing
- Swelling or inflammation of any part of the body.
Get the word of drug information
A rectal thermometer may be an accurate way to measure your body temperature, but it is the standard when it comes to monitoring your baby's temperature. Since many parenting books do not provide a detailed description of rectal measurements, the thought of taking your child's rectal temperature can make you nervous or scared.
But there is nothing to worry about. By following the correct steps, you can safely monitor your baby's temperature and get the correct reading. If you need more advice on how to monitor your child's rectal temperature, speak with your pediatrician, as he or she can provide further guidance on how to do this.
Frequently asked questions
Maybe. If your child is constipated, inserting a rectal thermometer in the same way as taking a temperature can stimulate bowel movements. However, it is important to speak with your pediatrician to manage your child's constipation and discuss the appropriateness of using a rectal thermometer.
Although rectal thermometers can be used from infancy to adulthood, many older children may not want to have their temperature checked rectally. You can stop using a rectal thermometer for your baby after three months, but make sure your baby is responsive enough to tolerate other thermometers.