Continuous glucose monitors, or CGMs for short, are life-saving devices used by people with diabetes.  

These tools help them better track their blood sugar levels and glucose trends over time and improve their time in range (TiR), glucose levels, and HbA1cs. 

CGMs are equipped with alerts and alarms that can let the user know when their blood sugar levels are becoming dangerously high or low. 

But how do you use a CGM—and how can this device improve your diabetes management? 

This article will tell you everything you need to know about CGMs and how best to use them. 

Woman wearing a CGM device near a ledge and looks out at the sunset.

What is a continuous glucose monitor? 

Continuous glucose monitors are small, externally-worn devices that a lot of people with diabetes use in lieu of manual blood sugar testing. 

They do not require too much input from the user and have been proven helpful in improving blood sugar control. 

In contrast to manual blood sugar checks, a CGM will automatically test the interstitial fluid (fluid found in the spaces around cells) that will approximate a blood sugar reading within 10% every 5 minutes, for up to 288 readings per day. 

This is a huge improvement over the ten or so times a person would normally manually test their blood sugar. 

Additionally, a CGM shows trend lines, so you can predict future blood sugars, plan meals, and exercise accordingly. Once you notice patterns, you can adjust your medications to stay on top of your management even more. 

A helpful tip is to set low and high blood sugar alarms that wake you up in the middle of the night so you can check your blood sugars and avoid emergencies. 

CGM technology is improving all the time. Dexcom, a popular CGM manufacturer, now has a product that comes with a Share feature. This allows people to share their blood sugar data with up to 10 remote followers—making this a great option for parents with children who have diabetes. 

Some CGM systems are now integrated with insulin pump technology, which can make insulin dosing adjustments based on blood sugar readings. 

Can anyone get a CGM? 

Eligibility for a CGM varies and depends on what type of health insurance you have. However, most state Medicaid programs, Medicare, and private insurance do cover CGMs for people with diabetes. 

Some plans will only allow people who inject insulin to qualify for a CGM.

Others will require the patient to manually test their blood sugar a certain number of times per day to qualify.  And some will require evidence of frequent hypoglycemic events or even hypo-unawareness. 

Other plans will cover a CGM for just about anyone with a diabetes diagnosis. 

It’s important to remember that CGMs are available by prescription only. 

Talk with your doctor if you’re curious about getting a CGM. If you qualify, they can help you get a prescription to try it out! 

There is also something called a “short-term” or “professional use” CGM where you can essentially borrow a CGM from your doctor’s office for a shorter period of time (72 hours or two weeks, for example), to simply track blood sugar trends to make management adjustments. 

This might be a great way to try a CGM before diving into actually buying a whole system. 

I qualified for a CGM! How do I use it? 

There are four different brands of CGM available in the United States currently: 

  • Abbott Libre
  • Dexcom
  • Medtronic
  • Eversense 

Each comes with its own pros and cons, so make sure to talk with your doctor to figure out which one will be most appropriate for you.

Some are more affordable than others, while others offer more features that may be more attractive to you as a patient. 

Only the Medtronic and Dexcom CGMs can be integrated with an insulin pumping system, so if you are on insulin pump therapy, that is something to consider.

Once you’ve decided which type of CGM you’d like to use, the following steps can help you get started.

Check your insurance coverage 

This is an obligatory first step (in the United States), but it’s crucial to see if your health insurance will actually cover the type of CGM you wish to use. 

You may have excellent coverage that doesn’t require any copayments or extra fees, but more likely than not, you’ll have to pay at least a small percentage of the cash price for a CGM. 

If you do not have health insurance, you will need to pay the total list price of the CGM. 

Fill your prescription 

Many CGMs are available as a pharmacy benefit, this means that you can take your prescription right to your pharmacy and pick up your CGM along with your insulin each month.

However, some health insurance plans require that CGMs are provided as durable medical equipment (DME). In this case, the patient must work with a third-party supplier, such as Byram or Edgepark. 

If that’s the case, your doctor will most likely send the prescription to them for you, and then a representative from a third-party supplier will organize your shipment and delivery. There is no cost for shipping these medical devices.

This can be trickier because sometimes there is miscommunication between your health insurance plan, your doctor, and these third-party suppliers. However, they try to make the process as seamless as possible for the patient. 

Attend all trainings

Usually hosted at your doctor’s office, these trainings feature a company representative who demos new insulin pumps or CGM supplies for you. 

However, more and more of these trainings are also available online for more convenience.

Companies like Dexcom, Abbott, and Medtronic make these training sessions easily available on their websites. 

Don’t overanalyze the data 

Are you all set up with your new CGM? Congrats! You have just taken a big leap in your diabetes journey that will hopefully have you feeling even better and healthier well into the future. 

A common issue that new CGM users often encounter is the urge to overanalyze the data. This causes them to over-correct both high and low blood sugar levels. This behavior results in more destructive blood sugar levels (hello, rollercoaster!) 

In fact, checking your CGM data trends too much can contribute to anxiety and diabetes burnout. 

Remember: it’s natural to see your blood sugar spike after you eat and drop while exercising. 

Don’t set your expectations too high when first starting on CGM therapy. There is a huge learning curve, and you need to learn how to make the system work for you. 

Avoid over-analyzing your CGM data by relying on your insulin pump (and its preexisting settings) to make dosing decisions for you instead of manipulating the numbers manually. 

Talk with your doctor if you’re struggling with CGM-induced anxiety. They can help you adopt healthy boundaries around technology. A mental health provider can also be a great resource for relief. 

Make CGM a part of your routine

CGM technology is an amazing addition to your diabetes toolbelt, but recognizing that it won’t solve all of your blood sugar woes is important. 

Habits like regular exercise, eating healthy, getting enough sleep, adjusting your medications as needed, and managing stress are also crucial components for living a healthy life with diabetes. 

CGM technology can empower you with making better dosing decisions—along with deciding when and how is the best way to exercise, and what foods and drinks your blood sugars are most sensitive to. 

Knowledge is power! Using CGM data to educate yourself on how your body reacts to certain foods, stress, and exercise can be extremely helpful.

Conclusion

Continuous glucose monitors, or CGMs for short, are powerful tools used by people with diabetes to better track their blood sugar levels in real-time. 

They also provide trending data over time, so people can better predict where their blood sugars are headed—and in response, build an exercise and eating schedule that supports their blood sugar levels. 

CGMs can improve blood sugar and HbA1c levels and vastly improve quality of life.

Make sure to check with your health insurance to see what type of CGM is covered (if any.). 

Talk with your doctor to see which brand of CGM is most appropriate for your care, as every brand has pros and cons. 

After filling your prescription and attending any mandatory training (offered both in-person and virtual), it’s important to not over-analyze the data. 

Remember that CGM technology is a powerful part of your diabetes toolbelt, but it isn’t the only tool that you’ll need to live a healthy life with diabetes. 

Continuing to exercise, eat healthily, manage stress, adjust medications as necessary, and get enough sleep are also pivotal to living well with diabetes.