What is the Dexcom G6 Continuous Glucose Monitoring (CGM) System?

The Dexcom G6 is Dexcom’s latest generation continuous glucose monitoring (CGM) system. Unlike previous generations, this CGM system is factory-calibrated—so no fingersticks are required.* The Dexcom G6 is comprised of a sensor, transmitter, and display device (receiver and/or compatible smart device)**. The system features a redesigned, one-touch auto-applicator and sleek, discreet transmitter. The Dexcom G6 sends glucose readings to a compatible smart device or the Dexcom receiver every 5 minutes. The Dexcom G6 is indicated for patients ages 2 and older.

*If your glucose alerts and readings from the G6 do not match symptoms or expectations, use a blood glucose meter to make diabetes treatment decisions.

First cleared by the FDA in March 2018 Trusted Source, the G6 was the first-ever 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 to do away with the requirement to take fingerstick tests to calibrate for accuracy.

What is the Dexcom G6 Continuous Glucose Monitoring (CGM) System?

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 like 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-a-day calibrations as previous versions did. That means it has a non-adjunctive 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 offered a whole new inserter design for the first time in many years. 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, pre-assembled 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. But there’s more! 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 prior to insertion, which triggers the “no calibration” functionality. Note that if this code is not scanned or entered, the sensor will require the daily calibrations every 12 hours, as was required with the 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 to the previous 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 Do-It-Yourself 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 ages 2 and older.

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.

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, and the graph with glucose value dots and other inputted data like insulin/carbs/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.

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.”

Both iOS and Android. The G6 app works with both Apple and Android, but not with every model. Here’s a list of specific 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.