Glucose Monitoring 101

You may have heard of ‘flash glucose sensors’ (FGS) or ‘continuous glucose monitors’ (CGM), but what do these devices actually do? How can they help people living with type 1 diabetes? And how do they work with Omnipod® Pod Therapy? Let’s find out!

What is a glucose monitor?

Flash glucose sensors and continuous glucose monitors allow users to check their sugar levels without having to use finger pricks.

Each device uses a sensor- a small, wireless device that you wear on your body- that reads your glucose levels via the fluid under your skin called “interstitial fluid”. This is slightly different from the blood glucose reading taken with finger prick testing as it lags behind blood sugar levels by up to 15 minutes.

You may still need to occasionally finger prick, for example, if what you’re feeling doesn’t match what your reading says or if you want to double check before treating a high or low sensor reading. This is why it’s important that you still get your diabetes kit on prescription including your blood glucose meter to let you do finger prick checks1.

What’s the difference between a flash glucose sensor and a continuous glucose monitor?

Flash glucose sensors are intermittently-scanned continuous glucose monitors (isCGM). This means that you need to wave (or scan) a device over the sensor to get the glucose reading.

A real-time continuous glucose monitor (rtCGM) automatically transmits the readings, via Bluetooth, to a receiver or smartphone every 5 minutes, 24 hours a day.  

How does a CGM help with type 1 diabetes management?

Flash or continuous glucose monitors take a sensor glucose reading from the interstitial fluid, just below the skin, and allow the user to see this information on a smartphone or other device.

They also offer the ability to see if glucose levels are high or low, rising, falling, or stable. You may hear this referred to as a “trend” and users can take action earlier if they notice glucose levels beginning to rise or drop. CGM graphs can help build a better understanding of a person’s glucose trends and what affects glucose levels.  

With a CGM and the latest FGS there is a function to set alarms and alerts for when your sugar levels get too high or too low.  

Dexcom G6 Dexcom G6

How does a CGM help with type 1 diabetes management?

The glucose information and trends give someone living with diabetes a greater picture of what their glucose levels are doing at any given time of the day. This information can be used to help inform treatment decisions - for example around when waking, eating, or during exercise.

Some CGMs will also alert you when your glucose is running high or low, or even predict hypoglycaemia in advance. This feature can help give greater peace of mind when it comes to hypoglycaemia or hyperglycaemia.

Research suggests that continuous glucose monitoring can help people with type 1 diabetes improve their time in range, as well as reducing their HbA1c without increasing the risk of hypoglycaemia.2, 3

Can I use a glucose monitor alongside a Pump?

The short answer is yes.

For example, any glucose monitor can be used alongside your Omnipod DASH® System to monitor your glucose levels. The user will manually input these readings into the Personal Diabetes Manager (PDM) for a meal or correction bolus.

The Omnipod® 5 System currently integrates with Dexcom G6 CGM to enable Automated Insulin Delivery (AID).

Real-time CGMs are an essential part of Automated Insulin Delivery (AID) or Hybrid Closed Loop (HCL) Systems, like Omnipod 5.

The glucose readings from the rtCGM are sent wirelessly to the Pump or Pod, where an in-built algorithm continuously adapts to automatically deliver basal insulin according to your personal needs. This may help to control blood glucose levels, reduce hypoglycaemia, and increase time in range4. We will cover this in much more detail in our What is Automated Insulin Delivery module. 

*Users still need to manually bolus for meals and corrections

Is Omnipod 5 right for me?

Find out more about the Omnipod 5 Automated Insulin Delivery System and how it works together with Dexcom G6 to incorporate your rtCGM data and trends to automatically adjust insulin delivery.

Frequently Asked Questions about CGMs

How does a continuous glucose monitor differ from finger prick testing?

How often do you have to change a flash or CGM sensor?

Where can I wear a CGM?

Can I share my Glucose data with Friends and Family?

What is the Omnipod 5 Automated Insulin Delivery System? 

Next up...

Automated Insulin Delivery (AID) is revolutionising the way people manage their type 1 diabetes. Let’s find out what it’s all about.

References and disclaimers:
2 Beck RW, et al. JAMA. 2017;317(4):371-378 via
3 Welsh, JB et al. Diabetes Technol Ther. 2019;21(3) via
4 ADA Standards of Medical Care in Diabetes – 2021. Diabetes Care. 2021;44(S1):S1-S232