CGM: Continuous Glucose Monitor
Today’s CGMs — continuous glucose monitors — put diabetes management into the 21st century. This small wearable device provides people with diabetes the blood sugar information we need to make daily management decisions.
Improving both our short and long-term health and safety, CGMs should be considered the standard of care for anyone of any age with any type of diabetes.
What is a CGM?
A CGM is a small wearable device that tracks your blood sugar levels in real-time throughout the day and night. At any moment, without pricking your finger, you can see not only what your blood sugar level is but also what direction it’s headed in.
With personalized settings, CGMs can alert you to high or low levels while also charting your blood sugar about every 5 minutes on a graph on your Smartphone or separate receiver device.
Compared to checking your blood sugar with a drop of blood on a test-strip, the information a CGM can provide both you and your healthcare team can help you adjust your diabetes management regimen and improve your overall safety around highs and lows.
*Watch this video to learn more about the differences between readings from your glucose monitor vs. a CGM sensor.
How a CGM Works
While each brand of CGM technology works slightly different, they have many similarities. (*Most of the details described below do not apply to Senseonics’ implantable Eversense CGM technology.)
- Most CGM sensors consist of three parts: sensor (which sits in the skin), the transmitter (sits above the skin), the receiver (either your Smartphone or a handheld device that receives blood sugar data).
- Most CGM sensors (a very thin wire-like piece) sit in subcutaneous tissue (body fat). The sensor is usually inserted with an easy at-home application device that inserts the sensor with a fine needle. The needle instantly retracts, leaving the sensor in place.
- The visible portion of a CGM is the transmitter, which is sits on top of the skin with an adhesive that holds the entire device in place.
- CGM sensors can be placed in several areas of your body, depending on what is most comfortable for the user: back of the arm, side/front torso, lower back, buttocks area, outer thigh, etc. Avoid spots where your body naturally bends a great deal, where clothing might cause irritation or be a burden.
- The process of inserting the CGM sensor is easy and virtually painless.
- Varying based on brand and model, most CGM sensors need to be replaced every 2 weeks.
The Benefits of a CGM
A few of the benefits of using a CGM include:
- Seeing your blood sugar level at any moment without pricking your finger
- Seeing the direction of your blood sugar: rising/falling, gradually/quickly
- Learning how/when your body responds to food, activity, hormones, stress, etc.
- Customizable settings to alert you when your blood sugar falls below a certain level
- Customizable settings to alert you when your blood sugar rises above a certain level
- Catch and treat high blood sugars sooner
- Catch and treat low blood sugars sooner
- Help you reach your overall A1c and blood sugar goals
- Learn what percentage of the day you are in/above/below your goal blood sugar ranges (also known as “time in range” or TIR)
- Can integrate with your insulin pump (with additional features for closed-loop systems)
- Share your CGM data with your healthcare team
- Share your real-time CGM data with family or friends to see at any time on their Smartphone
- Review your blood sugar levels at any time with helpful graphs and analytics
Research on the Benefits of Using a CGM
- Research shows people with Type 2 diabetes who are on multiple daily insulin injection therapies (MDI) and used a CGM lowered their average A1C from 8.5 percent to 7.7 percent.
- In contrast, those who tracked their glucose using a standard BGM were only able to lower their A1C from 8.5 percent to 8.0 percent. Better management = decreases the risks of complications.
CGMs Available Today
Here are today’s available CGM brands and models. This technology has evolved rapidly over the last decade, improving in ease-of-use, accuracy, and connectivity with other technology.
Abbott: Freestyle Libre 2 & Libre 14-Day►
Dexcom: G5 & G6►
Medtronic: Guardian Connect►
Watch this video to learn more about the differences between blood glucose readings and sensor readings, watch the video by FreeStyle Libre system below.
How do I get a CGM?
Getting a CGM starts with asking your doctor to write the prescription. Talk to your doctor about your device options and decide together which might be best for you.
Check what brands are covered under your insurance plan (including patients on Medicaid and Medicare). For example, Dexcom’s CGMs are covered by Medicare. Abbott’s FreesStyle Libre is also covered by Medicare for those who qualify.
To receive a CGM under Medicare or Medicaid, please contact your local state health exchange to check your eligibility.
Some brands also offer complimentary trial periods for new users, like the Hello, Dexcom or MyFreeStyle Program. The MyFreeStyle Program allows eligible people to try either the FreeStyle Libre 14 Day System or the FreeStyle Libre 2 system. After your eligibility is determined, you’d request a prescription from your healthcare provider and get guided support from 14 days of emails tailored to your personal journey.
Getting a CGM
While CGMs can help anyone improve their diabetes health, getting a CGM can come with some hurdles. Here are some tips for navigating that process.
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Using a CGM
CGM technology can provide you with so much more information about your blood sugar levels than a glucose monitor.
The Importance of “Time in Range” for Diabetes ManagementMany healthcare providers are embracing time in range (TIR) as an important measure in helping patients manage their diabetes. MORE
Lowering Your A1c with the FreeStyle Libre 14 Day SystemYour A1c helps you monitor your progress towards your glycemic goals. The FreesStyle Libre can help you get there. Read how this CGM can help you reach your diabetes goals.MORE
Using CGM to Reduce Low Glucose EventsAlways a little dizzy or shaky? Your blood sugar may be low. Read our article on how a CGM could help you reduce low blood glucose episodes.MORE
The Importance of CGM for Insulin-Dependent Type 2 DiabetesFor people with insulin-dependent Type 2 diabetes, a CGM can be the turning point in reaching your diabetes goals. Learn why these devices can work for you and make living with diabetes easier.MORE
The Value of Professional CGMNeed help with your diabetes routine? Consider trying professional CGM (P-CGM). You and your doctor can use it to learn more about your Type 2 diabetes.MORE
Sharing Your CGM DataYou don't need to do diabetes alone. If you wear a CGM, read about sharing your data with your friends and family who help you manage Type 2 diabetes.MORE
The Benefits of Time-in-Range for Type 2 Diabetes with DCES Megan MuñozLearn how time-in-range benefits people with Type 2 diabetes with diabetes care and education specialist, Megan Muñoz! MORE
Researchers Find That CGMs Provide Insight On The Progression Of Type 2 Diabetes Among Hispanic AdultsResearchers break down the importance of CGMs in understanding diabetes and how to tackle accessibility barriers among Hispanic adults. MORE
Real Life with a CGM: Stories & Interviews
Here are a few stories from people with diabetes and healthcare providers who’ve experienced the benefits CGM technology!