Glucose Sensors

What is a glucose sensor? 

A glucose sensor is an FDA-approved medical device for diabetes that continuously monitors blood sugar levels throughout the day. It is connected to a monitor that displays and stores the data making it easier to manage your diabetes. Additionally, some monitors can send alerts when blood sugar levels drop or rise beyond your custom thresholds. 

How does a glucose sensor work?

A tiny sensor is inserted under your skin and measures the amount of glucose between your cells. Readings are automatically taken every five minutes, and this information is both displayed and stored, usually on a monitor. Newer glucose sensors can now even display the data through an app on your phone. You will be able to see your current blood sugar level as well as trends or patterns in readings.

Where is a glucose sensor placed?

Glucose sensors are most commonly placed under the skin on the stomach or arms and are held in place by an adhesive patch. It is recommended that the sensors be placed:

  • In a spot that will be comfortable to wear 24/7 and will not be messed with during sleep
  • In an area that does not have loose skin, scar tissue, tattoos, moles, or noticeable veins
  • At least three inches away from an insulin injection site or insulin pump

Do glucose sensors need to be replaced?

In most cases, the sensors should be worn for 10-14 days before having to be replaced. This may vary depending on the brand and model you use, so please check with your doctor for the exact time frame.

Can a glucose sensor replace my glucose meter?

A glucose sensor may replace a traditional glucose meter in some cases as glucose sensors no longer require calibrations with fingerstick blood sugar checks. With these models, unless a blood sugar is very high or low, you do not typically need to complete a fingerstick blood sugar reading. Others require calibration and thus, it is important to continue taking your blood sugar with a finger stick a few times a day because it will help check the accuracy of your glucose sensor. Regardless, since the sensor continually takes readings throughout the day, having a glucose sensor will minimize the number of finger sticks needed daily, making it an easier option overall.

Can you use a glucose sensor with an insulin pump?

Glucose sensors can be linked to an insulin pump, allowing insulin to be automatically adjusted based on the sensor’s blood sugar readings. Please note that if you connect the two, this does not eliminate the need to continue to be aware of your blood sugar level. 

Are there different types of glucose sensors?

Glucose sensors are currently manufactured by four different brands: Dexcom, Abbott, Medtronic, and Eversense. While the features of each brand differ slightly from the other, they all consist of the three main components: 

  • A sensor is the small filament that is inserted into the skin and measures blood sugar levels.
  • A transmitter is the part of the sensor that sends the reading information to the monitor.
  • A monitor is a device separate from the sensor that stores and displays the information. 

How can I get a glucose sensor?

Glucose sensors can make managing your diabetes more manageable. However, they require a prescription, so if you think a glucose sensor might benefit you, please speak to your physician or endocrinologist. Our team at Inland Endocrine can help you get started – book an appointment with us today.


Dexcom. (2021, March 25). Where can I insert my Dexcom G6 sensor? 

Funtanilla, V. D., Caliendo, T., & Hilas, O. (2019, September). Continuous Glucose Monitoring: A Review of Available Systems. U.S. National Library of Medicine.

Russell, S. J. (2017, June). Continuous Glucose Monitoring. National Institute of Diabetes and Digestive and Kidney Diseases. 

U.S. Food and Drug Administration. (2017, November). Eversense: CGM Sensor Insertion and Removal Instructions.


Medically reviewed by:

Jodi B. Nagelberg, MD, MHA

Dr. Jodi Nagelberg is an endocrinologist, with board certification in Internal Medicine. She also holds a masters in Health Administration and Policy. She joins TeleMed2U as Endocrinology Director and supports our mission to increase access to healthcare for patients everywhere.

Postgraduate: University of Southern California Sol Price School of Public Policy Los Angeles, CA  Masters, Health Administration and Policy, 2011