Dexcom G6 Review: Everything You Need to Know

First cleared by the FDA in March 2018, the G6 was the first CGM to offer direct-to-smartphone app connectivity without requiring a separate receiver, although users can still opt to use one or the other.

It was also the first CGM to do away with the requirement to take fingerstick tests to calibrate for accuracy.

Here’s a breakdown of what the system entails:

Transmitter

This is the thin gray part that clicks on top of the sensor casing worn on the body. It functions as the brain of the system. The G6 transmitter is a third smaller, thinner, and lower profile than the previous model. It has a 3-month battery life.

With built-in Bluetooth connectivity, the G6 sends results every 5 minutes directly to a smartphone app, a separate receiver, or to compatible devices within 20 feet.

No fingersticks required

The G6 does not require once or twice daily calibrations as previous versions did. That means it has a nonadjunctive designation from the FDA, so it can be used in making insulin dosing and treatment decisions without a backup fingerstick test.

What’s awesome is that even though the G6 is factory-calibrated, Dexcom has built in the capability for users to still enter calibrations manually if they choose to do so (for extra confidence in accuracy).

Disposable auto inserter

The G6 offers a whole new inserter design. It’s a plastic, spring-loaded, self-contained auto-applicator that requires you to do nothing but press an orange button to inject a new sensor. It’s even good for one-handed insertions.

The sensors come in boxes of three, preassembled into the auto-inserter, so no needles are exposed. To insert, you pull the adhesive backing, place the unit on your skin, and push the button.

The disposal applicator piece will automatically separate from the sensor once it’s on your body.

Sensor code

Each Dexcom G6 sensor has a four-number code printed on that adhesive backing that you peel off before attaching the sensor to your body.

You need to enter that code into the mobile app or separate receiver device just before insertion, which triggers the “no calibration” functionality.

Note that if this code is not scanned or entered, the sensor will require daily calibrations every 12 hours, as was required with the previous G5 model.

10-day wear

The water-resistant G6 sensor is said to be more accurate and reliable and can be worn for 10 days compared with the earlier model’s 7 days.

There is now a hard shutoff at the 10-day mark, meaning you won’t be able to extend the sensor for prolonged wear, as many people did with previous versions.

The FDA actually laid this out in a letter to Dexcom describing requirements for the G6. There are some DIY methods to restart a sensor, but those are considered “off-label” and not endorsed by the FDA.

Young kids

The Dexcom G6 is approved for children ages 2 years and up.

Goodbye, Tylenol effect

No more interference from medications containing acetaminophen (Tylenol), which has been an ongoing issue in the CGM world.

The G6 has a special membrane on each sensor that eliminates the body chemistry interference from these medications, which previously could give false high glucose results.

Predictive alerts

You’ll get an “Urgent Low Soon” alert whenever the sensor picks up that glucose levels are falling fast and predicts you’ll drop to 55 mg/dL within 20 minutes.

This alert is required by the FDA and cannot be turned off, unlike the other G6 alerts and alarms that can all be silenced.

Customizable alerts

You can set different alert preferences for times of day or night. There’s a “Do Not Disturb” feature for audible or vibration alerts, though the “Snooze” feature is disabled on important alerts like “Urgent Low” and “Sensor/Transmitter Failure.”

Dexcom G6 mobile app

After a 2-hour warmup period without any data, the G6 mobile app starts showing glucose results. It displays a circle with the current real-time glucose level and appropriate Gray/Red/Yellow color code depending on whether you’re “In Range,” “Low,” or “High.”

A little arrow points in the direction you’re trending. The graph with glucose value dots and other inputted data like insulin, carbs, or exercise is displayed below that.

Want to view more than the past 3 hours of CGM data? Turn your smartphone horizontally to see up to 24 hours of data and scroll back accordingly. Data can be shared via the separate Dexcom Follow app with as many as 10 people, and with a doctor’s office through the Dexcom CLARITY platform.

Both iOS and Android

The G6 app works with both Apple and Android smartphones, but not with every model.

Here’s a list of compatible devices, although it’s not entirely clear which devices or wearables are seamlessly compatible from the get-go. Also, Dexcom says the G6 won’t yet send data directly to an Apple or Android watch without the phone.

See this nifty G6 simulator app available on both iTunes and Google Play to take the Dexcom G6 app for a trial run.

The standard measurement of CGM performance is known as the mean absolute relative difference (MARD). With this measure, the lower the number, the better the accuracy.

Clinical data for the Dexcom G6 shows it has a MARD of 9 percent with sustained accuracy over the time a sensor is worn. That puts it ahead of all its direct competitors.

However, individual users’ experiences may vary. Many people who have used both the Dexcom G6 and Abbott FreeStyle Libre 2 report comparable accuracy.

To view glucose data trends and send reports to your healthcare professionals, you’ll want to use Dexcom CLARITY, the company’s web-based software. It’s available both online and through the Dexcom G6 smartphone app to customers at no cost.

On the G6 app, you simply turn the orientation of your smartphone to horizontal view, and you’ll see a green icon with four vertical lines in the upper right corner. Clicking on that icon takes you directly to the Dexcom CLARITY app.

CLARITY shows your average glucose for any number of different days, reports for the past 24 hours to 3 months, and comparison charts to help you see how you managed during different periods.

For example, if you started on a new insulin pump 1 month ago, you can easily view how your CGM data for the past month may differ from the weeks or months prior.

Two other popular features of CLARITY include:

• Time in Range view: It shows the percentage of time your glucose levels are in low, target, and high ranges. The default “in-target” range is 70 to 180 mg/dL, which may not be what you set for your CGM, so you can change the Dexcom CLARITY ranges in Settings to your preferred targets.
• Glucose Management Indicator (GMI): This approximates the laboratory A1C result you might expect based on your average glucose from the most recent 12 days of CGM data. It’s not a precise prediction, but many use this feature to help them get a better idea of where they stand on that 3-month average result.

You can also grant access to your CLARITY data to your doctor. Simply authorize this via the app or on the CLARITY website, which allows your doctor to log in at no cost and view your data.

Notably, using the CLARITY overview report is billable to insurance, so your doctor can get reimbursed for interpreting and reviewing your CGM data through Medicare or private insurers. The billing code (aka CPT code) is 95251.

A large array of private insurers in the United States cover Dexcom CGMs. As of mid-2022, Medicare covers the Dexcom G6 as well.

Of course, benefits vary by plan, so you’ll need to check with yours. Just remember that you’ll need a prescription for the G6 transmitter as well as the box of sensors, so you’ll have to work with a healthcare professional before purchasing.

Until spring 2021, Dexcom sold its systems and supplies directly via its website. But the company now works with distributors like Edgepark for online ordering.

Short answer: The Dexcom G6 is a great tool for any adult or child with any type of diabetes, including those who are pregnant or have gestational diabetes, given how important tight glucose management is during pregnancy.

The benefits of CGM use are well documented. Using a CGM can:

• help avoid severe high or low blood sugars, especially immediately dangerous hypoglycemic events
• help guide insulin dosing and safeguard users from mistakes
• provide a sense of safety and security for people who don’t feel dangerous lows coming on (hypoglycemia unawareness)
• increase glucose “time in range” for better diabetes management
• let users see and learn from the direct impact of their food and physical activity on their body

In fact, CGM is so powerful for improving overall health outcomes that it’s quickly becoming a consumer wellness product.

There’s little doubt that all people with diabetes can benefit, but recent studies show that CGMs may be especially beneficial for certain groups, including teens, young adults, and older adults. This is likely due to the convenience these devices provide.

When the FDA approved the G6 in 2018, the agency created a brand-new category of device that it refers to as “iCGM,” or integrated CGM — a system designed to connect directly with other compatible devices, such as a smartphone, insulin pump, or other wearable device.

Devices that currently work with the Dexcom G6 include the latest Omnipod tubeless insulin pump and the tubed Tandem t:slim X2 insulin pump with Basal-IQ and Control-IQ closed loop features.

Not sure whether your device is compatible with Dexcom G6? You can check that out here.

What’s exciting is that the future Dexcom G7 model will have even more advanced features and integration with automated diabetes management systems.

Based on customer reviews from consumer sites like the Better Business Bureau and Trustpilot, people are generally satisfied with the Dexcom G6. They find that it helps them improve and manage their glucose levels. The most common complaints are those relating to customer service, insurance claims, and deliveries.

Many online reviewers say the Dexcom G6 is extremely reliable and accurate. But others report the transmitters do not always last the full 90 days and sensors also fail early before the full 10 days.

As a result, a common complaint is having to spend a lot of time contacting Dexcom’s technical support, either by phone, text, or online, to get a replacement sensor sent within 3 to 5 days.

Users often share the following tips for the G6:

• Make sure you’re hydrated to ensure better glucose data and sensor reliability.
• Use some nasal allergy spray on your skin and a medical adhesive wipe to prepare for insertion. This helps avoid skin irritation and keeps the sensor on longer.
• Even though you can enter fingersticks to calibrate the G6, it’s not required. Entering multiple results in a short period of time can cause the CGM to get confused. Wait at least 30 minutes if it loses a signal or is trying to recalculate your glucose levels to see whether it can re-establish a solid connection with accurate data.

There are several other CGM systems on the market that are similar to the Dexcom G6. Here are some to consider:

A key part of managing diabetes involves checking blood sugars, or glucose levels.

In type 1 diabetes (T1D), a person’s pancreas does not produce insulin. In type 2 diabetes (T2D), the body may not make insulin correctly anymore.

For either T1D or T2D, making sure glucose levels stay as level as possible is the goal. Sometimes insulin or diabetes medications are used based on the type of diabetes and personal needs. Many factors, such as food, exercise, insulin, medications, stress, etc., affect glucose levels.

Glucose level targets may vary for everyone based on their unique needs.

But the 2022 standards from the American Diabetes Association (ADA) advise that the typical blood sugar range for (nonpregnant) adults with diabetes are:

• between 80 and 130 mg/dL before meals
• lower than 180 mg/dL within 1 or 2 hours after eating

Ranges vary for children younger than 18 years old, older adults, and those with chronic medical conditions or gestational diabetes.

You can always talk with your doctor and diabetes care team about your personal goals for glucose levels.

But meeting with your diabetes care team and endocrinologist may be especially helpful if you’re experiencing any trends in higher or lower glucose levels, particularly if you experience any hyperglycemia symptoms that might signal dangerous diabetic ketoacidosis.

If you’re interested in trying out the Dexcon G6 CGM before buying one yourself through insurance, you may also want to talk with your diabetes care team about the possibility of using a “blinded” professional version through their office.

This would allow your care team to view your glucose levels and patterns, but it would not give you access to that data alone.

How long does the Dexcom G6 device last?

You can wear the Dexcom G6 CGM on your body for up to 10 days before needing to replace the sensor. However, you may lose the Bluetooth data signal at times.

The sensor can also fail early before that 10-day wear time is finished.

The Dexcom G6 uses a separate transmitter that clicks into each sensor on your body, and the transmitter lasts for 90 days.

Do doctors recommend the Dexcom G6?

Yes. Doctors recommend CGM technology (including the Dexcom G6) for people with type 1 and type 2 diabetes because it provides a more complete picture of glucose trends than traditional blood sugar meters.

Do you need an internet connection to use the Dexcom Follow app?

Yes, you need an internet connection (either through Wi-Fi or a cellular data connection) for both the Dexcom Share app as well as the Dexcom Follow app to work correctly.

What does the Dexcom G6 cost?

You can purchase Dexcom G6 supplies in large retail pharmacies across the United States, including CVS, Rite Aid, and Walgreens. Cash prices vary. Most locations quote the price for a Dexcom G6 transmitter at just under $300, while a three-pack box of G6 sensors runs roughly $400.

Rough retail costs per year without any insurance factored in:

• a total of $1,200 for Dexcom G6 transmitters (each lasts 90 days, so four transmitters per year)
• a total of $4,800 for a box of three Dexcom G6 sensors (each sensor lasts 10 days)
• estimated total: $6,000 per year, or $500 a month

Dexcom G6 supplies are also available at Costco, with discount prices for store members who also sign up for Costco’s free pharmacy program.

The Dexcom G6 is the latest and most popular CGM on the market from a company that’s been developing CGM technology for nearly 20 years.

It offers real-time glucose data, complete with a range of alarms and customizable alerts to predict dangerous out-of-range glucose levels, and also allows for more proactive diabetes management.

With its easy-to-use form factor, high accuracy ratings, and compatibility with other diabetes devices, the Dexcom G6 can be an excellent choice for anyone with diabetes to consider.

However, it can be quite costly as well as frustrating when the product doesn’t deliver as promised.