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Managing diabetes requires constant vigilance — watching what you eat, getting exercise and monitoring your blood glucose.

However, continuous glucose monitoring technology can automate one of those things — testing blood sugar.

A continuous glucose monitor (CGM) device measures your glucose levels automatically all day and night, some will even alert you when levels are too low or high and helping you to notice trends and patterns.

The traditional way of checking blood sugar has been to prick your finger, use a glucose meter and record the data. Depending on the type and severity of your diabetes, this could be more than eight times a day.

CGM technology, both when paired with an insulin pump and alone, virtually eliminates finger sticks. More important, it can actually help improve your hemoglobin A1C (the measure of your average blood glucose).

At the University of Maryland Center for Diabetes and Endocrinology, our diabetes specialists work with the latest technology for continuous glucose monitoring and insulin pumps and can help you choose the right device for your daily life.

How Continuous Glucose Monitoring Works

With constant glucose monitoring, a small sensor is inserted under the skin, and typically a transmitter is then attached. (However, some systems, like the 14-Day FreeStyle Libre, combine the sensor and transmitter.)

The sensor measures your blood sugar levels, and the transmitter sends the data to a device. Depending on the specific type of CGM you choose, this device could be a receiver for specifically designed for your CGM, but it could also be an insulin pump or even your smartphone. When a CGM works with an insulin pump, this is sometimes called an artificial pancreas or a closed-loop insulin pump.

The data from the sensor can be uploaded to a web platform that you can share with your endocrinologist or diabetes educator. Together, you see the trends that influence your blood sugar and develop a plan to better manage your diabetes.

The site of the disposable sensor insertion has to be changed every 3 to 14 days, depending on the system. Typically, the transmitter is reused for several months.

Artificial Pancreas

Until recently, a CGM could only alert you when your blood sugar levels were changing, and you would have to use your insulin pump or inject insulin separately.

New technology has improved the accuracy of the CGM's measurements and linked the two devices. Your CGM can alert your insulin pump to adjust your background dose of insulin based on your current glucose level.

This type of system helps keep your blood sugar from going too high or too low. It will stop delivering insulin when your levels are going low too rapidly, often before you even feel the effects of low blood sugar.

Who Can Benefit From a CGM

People with both type 1 and type 2 diabetes can use a CGM. Typically the technology is most beneficial to people who need to check their blood glucose multiple times a day or whose blood sugars fluctuate between high and low frequently.

Continuous Glucose Monitor Cost

If you have type 1 diabetes, your medical insurance may cover all or some of the cost of a CGM system (sensors, transmitters and receiver) and for an insulin pump and its supplies. Many health insurance companies will also pay for this technology for type 2 diabetics, if they determine it medically necessary for managing your diabetes.

At UM CDE, our endocrinologists, diabetes educators and staff will help you decide on the right system for you and navigate the complexities of getting it approved. Our diabetes education program includes a class on insulin pump therapy that can help you decide if an artificial pancreas is right for you.

Call for an appointment at 443-682-6800.