Skip to content

CGM FAQs

What CGMs does Loop work with?

Loop 2.2.x works Dexcom G4 with share, G5, G6, Share and the Medtronic CGM systems compatible with Looping pumps.

Loop dev works with G5, G6, Share, Nightscout and the Medtronic CGM systems compatible with Looping pumps. A customization can be applied to work with some Libre sensors.

Read the details here.

Do I need wait for a new sensor session to start Loop?

No, you can start Looping mid-sensor session. There's no need to do anything special with regards to your CGM session when starting or ending Loop use.

What do I do when sensor is in warm-up?

Loop will stop automatically adjusting insulin when the most recent glucose value is older than 15 minutes. This is indicated by seeing three dashes in place of the glucose reading on the HUD.

  • With Loop 2.2.x or Loop dev, enter a fingerstick glucose value in Apple Health to enable Loop to provide updated projections and loop briefly

  • With Loop dev, a HUD status row message of No Recent Glucose is displayed, making it easier to add the fingerstick value directly in Loop, which also saves it in Apple Health

With no recent glucose readings, your pump resturns to the scheduled basal delivery (within 30 min or less).

Loop continues to accept manual bolus commands. With Loop dev only, Manual Temp Basal can also be commanded.

What do I do when I switch transmitters?

When you change transmitters, you will need to update the transmitter ID in your Loop settings. The instructions for Dexcom are provided below:

  • In Loop, select the Delete CGM button at the very bottom of the CGM info page
    • You cannot just edit the line with your old transmitter ID
  • Follow the Dexcom instructions for pairing the new transmitter
  • In Loop, add CGM and select the Dexcom system again
    • Enter the new transmitter ID

img/delete-cgm.jpg

If you don't update your transmitter ID when you change active transmitters, and you included your Dexcom share credentials, then Loop uses your Dexcom Share server to get your CGM data and will not work without cell or wifi connection. When Loop is using data from Dexcom Share servers, a small cloud will appear above the BG reading in Loop and should tip you off that maybe you forgot to update your transmitter ID. It's best not to enter Share Credentials. This makes it really obvious that you need to update the CGM settings in Loop at transmitter change time.

Can I use Libre sensors with a reader like Miao Miao?

If you want to use a Libre sensor you will need to modify Loop to accomplish that use. Loop code does not natively support that sensor, nor readers.

With Loop dev, a customization can be used to support some Libre sensor CGM.

Can I use Eversense?

Eversense does not write to Apple Health. The BT communications protocol been not been reverse engineered as was done with Dexcom. There is a method to upload Eversense to Nightscout using an Android phone.

With Loop dev, you can use Nightscout as a CGM to Loop with Eversense, but that requires internet access.

Can Loop read CGM data from Nightscout?

Some versions of Loop can read CGM data from Nightscout.

  • FreeAPS fork of Loop 2.2.x
  • Loop dev

Loop 2.2.x does not read CGM data from Nightscout.

What other CGM apps can be used to Loop?

Please read the docs for xDrip4iOS and Glucose Direct. You must build these apps yourself to Loop; you cannot use the TestFlight pre-built versions. These can be used with the FreeAPS fork of Loop 2.2.x and, after applying a code customization, with Loop dev.

Back to top