Dexcom CGM Options

This page provides information on the four official Dexcom CGM options, as well as the Anubis transmitter, which many Loopers use in place of the G6:

1. ONE and ONE+
2. G6
3. G7
   • G7 Troubleshooting
4. Comparison Chart
5. Code Conversion Table

Dexcom ONE and ONE+

Dexcom One and Dexcom One+ are newer CGM options from Dexcom, and are intended to be more affordable and accessible options for people with diabetes.

While Dexcom ONE is a simpler version of the G6, Dexcom ONE+ is a simpler version of the G7.  They are directly compatible with Loop 3.4.x. For Dexcom ONE, just select the G6 as your CGM. For Dexcom ONE+, just select the G7 as your CGM.

See the comparison chart below to compare the 4 official Dexcom CGM offerings to each other, as well as to the Anubis transmitter.

Dexcom G6

See the comparison chart for information on the G6.

Dexcom G7

The G7 is one of Dexcom’s newest products.  In addition to the information in the comparison chart, there are 2 other important G7 features that deserve attention.

1. The G7 can send readings directly to newer Apple watches.  However, you cannot Loop from your watch without your phone nearby, so this feature has limited application to Loopers.  To use direct-to-watch, your
   • Dexcom G7 app must be version 2.2.1 or higher,
   • Apple Watch Series 6 (or newer) must be running watchOS 10 or later, and
   • iPhone must be running iOS 17 or later.

   If you meet all of these requirements, the one Loop feature that you might find helpful is the Manual Temp Basal, which is an open loop override that allows you to set your basal rate and walk (or run or swim) away from your phone.  You won’t have any control over Loop while you’re away from your phone, but you’ll have convenient access to your blood glucose using Dexcom direct-to-watch.

2. The G7 app is geo-fenced, so if you’re traveling outside of your home country and your phone is lost, stolen, broken or goes for a swim, or the app fails, you will not be able to reinstall the G7 app (unless you have a computer with you and use a VPN to return to your home country).  If you are without a computer or don’t want to use a VPN, you should call Dexcom customer support and ask for help to install the G7 app (warning: they won’t be able to help you, but they’ll log the call by an angry consumer).
   If you don’t have a computer, or a different Loopable CGM (like the G6 or One or One+), you have two options for continuing to Loop, and both involve manually entering glucose readings into Loop :

• • Test blood glucose using a meter
  • Switch to the Dexcom G7 controller

Be sure to have a back-up strategy when you’re traveling internationally.

Dexcom G7 Troubleshooting

There are reports of G7 losing connection to both Loop and Trio.  These steps should help resolve this issue.  

1. Write-down the 4-digit sensor number from the Dexcom app.
   • G7 > Connections > Sensor
   • You may not need this sensor number, but it’s better to capture it just in case
2. Quit both your Loop/Trio app and G7 app
3. Forget all Bluetooth connections that start with DXCM
4. Open G7 app
5. Wait up to 5 minutes – you should get a new pairing request from G7 – accept it
6. Open your Loop/Trio app
7. Wait to see new value come in 

Note that Loop/Trio will not backfill the missing G7 data that came in while Loop/Trio was closed.

Comparison Chart

* Dexcom G7 has more alarm options than ONE+, and it connects with Tandem t:slim X2 insulin pump and lifestyle apps. The G7 is geofenced and the ONE+ is not.
** Anubis has 2 parameter options:  Default Parameters and Extended Parameters.  If you choose the Default Parameters, then Anubis will act just like a G6 transmitter.  To utilize the features in this chart,  you need to select Extended Parameters.

Dexcom ONE Calibration Code Conversion

Dexcom ONE sensors can be used with G6 transmitters and vice versa. However, the calibration code used must be converted to a different value when your sensor and transmitter are not of the same type. These calibration codes are definitely useful for anyone using the Official G6 App with an Anubis transmitter and Dexcom ONE sensors.

Behind the calibration codes are some calibration parameters, which the app sends to the transmitter. Dexcom G6 and ONE use different codes, but the same parameters – see the cross-reference table below.

xDrip and xDrip4iOS already have native support for both so these codes are not necessary for those users.

Sources for this information include a Reddit Comment in the subreddit for Dexcom and Followers of Anubis

No guarantee for accuracy.