Formulary

6.1.7 Continuous Glucose Monitors (CGM)

First Line
Second Line
Specialist
Hospital Only

The routine commissioning of continuous glucose monitors (CGMs) is accepted in Devon only in line with specific criteria; CGMs are not routinely commissioned for use outside these patient groups (refer to Commissioning Policy for initiation and continuation criteria).

A range of rtCGM devices are available, it is expected that a clinically appropriate device with the lowest cost is chosen (taking into account acquisition and ongoing running costs).

NICE advises that people who are using CGM (and their families or carers) will still need to take capillary blood glucose measurements to check the accuracy of their CGM device and as a back-up (for example when their blood glucose levels are changing quickly or if the device stops working), although they can do this less often. GPs should consider reducing the number of testing strips and lancets the patient requires in combination with a continuous glucose monitor.

Please refer to DVLA guidance regarding the use of real-time CGM (rtCGM) and intermittently scanned CGM (isCGM, also referred to as “flash” glucose monitors) when driving.

GP prescribable real-time CGM (rtCGM)

GP prescribable rtCGM is routinely commissioned for ALL patients with type 1 diabetes (or type 3c diabetes who are treated with insulin).

GP prescribable rtCGM is also routinely commissioned as an alternative to intermittently scanned continuous glucose monitoring (isCGM) for patients who meet the isCGM eligibility criteria in the policy if it is available for the same or lower cost.

Diabetes specialists* will provide appropriate patient training (and a route for ongoing support), supply the initial sensor and transmitter and ensure that this is linked with the patient’s smartphone or reader device, and ensure that the patient has sufficient sensors to last until the GP is able to provide ongoing prescriptions.

Following initial supply by the specialist*, the GP may be asked to prescribe rtCGM sensors on an ongoing basis.

* This includes primary care diabetes professionals with suitable knowledge and experience of rtCGM.

Dexcom ONE
  • CGM system (“starter kit”)
    • 1 x 10-day sensor, 1 x sensor applicator, 1 x 3-month transmitter (£41.00)
  • Interstitial glucose sensor (10 days use per sensor)
    • 1 x sensor with single use applicator, (£23.00 = one sensor, annual = £839.50)
    • 3 x sensors (plus 3 single use applicators) (£69.00 = 3 sensors, annual = £839.50)
  • Transmitter (3 months use per transmitter)
    • 1 x transmitter (£18 per transmitter, annual = £74.00)
  • Annual cost for comparison of this system (sensors plus transmitters) = £911.50

Notes

  1. Can be used by people aged 2 years and older, including pregnant women
  2. If glucose alerts and readings from Dexcom ONE do not match symptoms or expectations, use a blood glucose monitor to make diabetes treatment decisions
  3. Device compatibility with the patient/carer’s smartphone or tablet can be checked on the manufacturer’s website
    1. If the patient/carer does not have a compatible smartphone or tablet, a separate reader device may be required. This should be supplied by the initiating clinician
  4. Some smartphone settings may prevent correct system operation; refer to manufacturer’s website / product user guide for more information
  5. Each SENSOR last for ten days
  6. The TRANSMITTER lasts for three months (it may be reused for multiple sensor sessions). Dexcom ONE tells users when the transmitter will need to be replaced, starting 3 weeks before. 
  7. Any patients who are experiencing issues with their sensor, transmitter or reader should contact the Dexcom Technical Support Team using the Support Request Form via the Dexcom website (here) or by telephone on 0800 031 5761
  8. The routine commissioning of GP prescribable rtCGM is accepted in Devon for all patients with type 1 diabetes (or type 3c diabetes who are treated with insulin), and patients with type 2 diabetes who are treated with multiple daily insulin injections and who meet the criteria specified in the policy (see Commissioning Policy for more details)

Intermittently scanned CGM (isCGM)

A 6-month trial of intermittently scanned continuous glucose monitoring (isCGM) is routinely commissioned for patients with type 1 diabetes (or type 3c diabetes who are treated with insulin), and patients with type 2 diabetes who are treated with multiple daily insulin injections and who meet one or more of the criteria specified in the Commissioning Policy (updated December 2022)

The commissioning policy also details specific continuation criteria which must be met in order for continued use of an isCGM device. On completion of the trial, the initiating clinician should undertake a review to assess suitability for continuation against the specified criteria.

Diabetes specialists* will provide appropriate patient training (and a route for and ongoing support), supply the initial sensor and ensure that this is linked with the patient’s smartphone or reader device, and ensure that the patient has sufficient sensors to last until the GP is able to provide ongoing prescriptions.

Following initial supply by the specialist*, the GP may be asked to prescribe isCGM sensors on an ongoing basis (including during the 6-month trial period).

* This includes primary care diabetes professionals with suitable knowledge and experience of isCGM.

FreeStyle Libre 2
  • Interstitial glucose sensor (14 days use per sensor)
    • 1 x 14-days sensor with single use applicator (£35.00 = one sensor, 28 days = £70.00, annual = £912.50)

Notes

  1. Can be used by people aged 4 years and older, including pregnant women
  2. The FreeStyle Libre 2 system has the option of customisable, high and low glucose alarms (via the LibreLink app or Libre 2 reader); once alerted by the alarm the patient must scan the sensor to get a glucose reading
  3. Some smartphone settings may prevent correct system operation; refer to manufacturer’s website / product user guide for more information
  4. A finger prick test using a blood glucose meter is required if a HI or LO reading appears on the reader or if glucose readings and alarms do not match symptoms or expectations (refer to user manual)
  5. Any patients who are experiencing issues with their sensor or reader should contact Abbott Diabetes care directly for a replacement (Manufacturer contact number/patient care line: 0800 170 1177)
  6. The routine commissioning of isCGM is accepted in Devon for patients with diabetes mellitus only in line with specific criteria (see Commissioning Policy for more details)

Secondary care procured real-time CGM (rtCGM)

A range of rtCGM devices are available, it is expected that a clinically appropriate device with the lowest cost is chosen (taking into account acquisition and ongoing running costs).

A 6-month trial of a secondary care procured rtCGM is routinely commissioned only for patients with type 1 diabetes (or type 3c diabetes who are treated with insulin) who meet one or more of the criteria specified in the Commissioning Policy.

The commissioning policy also details specific continuation criteria which must be met in order for continued use of a secondary care procured (non GP prescribable) rtCGM device.

It is expected that at each review consideration is given to stepping down to lower cost (e.g GP prescribable) forms of glucose monitoring wherever clinically appropriate or where the ability to recognise and/or communicate about symptoms of hypoglycaemia has significantly improved.

These devices (including Dexcom G6 & G7, Medtrum TouchCare, Medtronic Guardian, and Freestyle Libre 3) are only available via the secondary care NHS supply chain; GPs are unable to prescribe these devices.

MHRA Device Safety Information (May 2021): Dexcom G6 Sensor: Untested barrier methods to reduce skin reactions:

  1. Some users of the Dexcom G6 continuous glucose monitoring system have experienced adverse skin reactions under the sensor, including hypersensitivity reactions.
  2. Use of barrier methods or patches is not recommended as this may affect the performance of the device.
  3. Identify patients who have skin reactions and consider whether continued use of this device is suitable for these patients. Consider use of alternative glucose monitoring systems for these patients.
  4. Report skin reactions to the device manufacturer and through your healthcare institution’s local incident reporting system and/or the national incident reporting authority