Libre Saying it's a CGM

I have nothing against a Libre. I wore one for years and was completely happy when I did so. And when I switched to a Dexcom I didn’t see a huge difference between them except I could calibrate my Dexcom instead of just adding numbers to my Libre reading to make it more accurate. I use one on my dog now and it drastically helps.

I also think the Libre is a wonderful thing as the Dexcom is so much more expensive here, so the Libre is much more affordable especially if you don’t have insurance that pays for these things. (In Europe and the UK the Libre is 96 pounds a month and the Dexcom is 159 or ($175) a month when you self fund, which a majority do.)

But I wasn’t using Dexcom to it’s full advantage at the beginning. The alerts were just annoying to me. But then I figured out how to use it to my advantage, of letting me know before I got out of range so I could do something about it sooner. And add the important calibration ability I am definitely in the Dexcom camp.

Because I still use it for my dog, and I still love it and I still get random communications from them.

I just got one. I’m thinking this is push back as in the UK and here in the USA a lot of us have been referring to the Libre as a FGM or Flash Glucose Monitor. That it’s not a true CGM. I guess Libre doesn’t like that. It really doesn’t say much except they are a CGM.

This is the first part, basically the whole message as it has a graph and chart too.

The FreeStyle Libre platform is a continuous glucose monitoring (CGM) system that continuously measures your glucose level around the clock,* with up to 10 or 14 days of sensor wear, based on product. CGM automatically tracks your glucose levels throughout the day and night,* so you can see your glucose levels in real time and review your glucose trends. When you use a blood glucose monitor (BGM), you need to do multiple fingersticks a day to closely manage your glucose.

The CGM sensor reading taken by the FreeStyle Libre platform and the blood glucose reading taken by a BGM may not always be the same. Even though BGM and CGM glucose readings may not always match, sensor readings from the FreeStyle Libre platform can replace fingerstick readings.†

In addition to providing current glucose readings, CGM also lets you know where your glucose has been, and where your glucose is going.

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I think Libre 14 day can be called cgm because MARD rating is now in range with G6.

Good comparison here.

I loved the Libre but Dex is better because I can take more insulin and not be worried. I’m really sensitive to even one unit, and never know how things will react. The new Libre I believe, is on hold in the US due to the virus issues going on in the world.

You raise an interesting terminology point.

It might be splitting hairs because we all know how the two devices differ.

Libre is a CGM in the fact that you can access continuous data, but you do not have real time access to continuous data.

You can access continuous data from a PC when you upload data from the device, right?

But, while you are walking around wearing it, you can only access discrete data - 1 data point at a time.

So, in the strictest terminology and definition, it might be considered a Discrete Glucose Monitor in real time with the ability to access continuous data at a later time.

Dexcom is an absolutely continuous, real time glucose monitor.

@mohe0001 With a reader it still has a small graph and you can look at daily graphs and a logbook of scans.With the ap on the iphone you can access all the charts etc.

But there has been a trend, more so in the UK to call the Libre a FGM. because until you scan it, you don’t have the readings or the alerts. I think Libre is trying to squelch the term, especially since they are supposedly coming out with one with alerts.

A lot of UK get themselves a Miao Miao when they have a Libre.

When you scan it, do you get 1 number or lots of numbers showing a trend?

You see continuous data when you scan, therefore I would call it a CGM. Otherwise we are really splitting hairs.

I’ve never actually used one. Thanks for helping to explain the difference.

You get one number with a graph. but you have a choice on the reader to review data. That data has charts of daily graphs and a logbook of all the scans.

But the ap on the iphone is more like Dexcom Clarity…

I’m not sure…

You can count the number of blood sugars if the data is discrete.
If you cannot, then the data is continuous.

In the most technical sense, both of them are discrete.

The one on the right. The Libre gives graphs and a number every time you scan the sensor. There are 2 ways the Libre differs from a dexcom. You cannot calibrate it if the readings are off and there are no alarms for high or low BG. The Libre 2 which is not yet available in the U.S. will include alarms for highs and lows.


What does it matter whats it’s called - 15 years ago you would have killed for it and now one letter matters.

My wife uses it - it’s fantastic

If you want to spend your day with dex and transmitters and broken wires and drained batteries and not working good for a day and half - have at it. Not to mention the shorter time and lousy customer service.

You forgot about when you put the test strip in, you take the transmitter out, you put the transmitter in the microwave, and you make a sign on the microwave not to use it while you restart the sensor on your phone and hope you didn’t wait too long… I think anyone who wants alarms on their libre knows to buy the miaomiao2 for about $190 after shipping and that’s a one time purchase…less than one 3 month disposable Dexcom trsnsmitter


Having alarms was a big reason I decided on Dexcom. I’ve had a couple ER trips in the past 40 years for hypos and I don’t want to put my family through any more if I can avoid it.

At the other end of the spectrum in how folks think about CGM’s: my friends with T2 whos endos gave them a week+ run with a CGM actually had no way of looking at their CGM data during that time. It’s not read out until they go visit the endos office. It seems these “Professional” units have as a selling point of not letting the patient look at the data. To say this is a different way of thinking… WOW!

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Interesting. The new libre 2 is comparable to the dex and does not require a third party bluetooth adapter. In fact, the 14 day libre can be calibrated using bluecon or miao miao app. I use to use the dex only to find out it is so much more expensive. I loop with the libre and which I calibrate with xdrip. Dex will appeal to those who have insurance and not self pay. . Sad that libre 2 is not cleared in the US yet. People are clamoring for it. It is simple economics. Dex has proprietary integrations they want to keep which drives a high price to pay.