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Libre Sensor 2 - PLEASE BE CAREFUL - Recent Issues

Thanks @Westley. Your suggestion to change sensors in the morning is a good idea but that's what I already did with this one. I hate not knowing what actually happened but I don't what the answer is when the sensor and blood test kit disagree with each other so much.

I've had the sensor on about 24 hours now and I think it's accurate, so I guess I'll leave it on and trust it. It's just kind of horrible not knowing if I caused myself brain damage last night or not.
 
RobertJ said:
I've had the sensor on about 24 hours now and I think it's accurate, so I guess I'll leave it on and trust it.
Click to expand...
Do you give the sensors time to bed in?
Many of us find that our bodies are not happy with an alien object inserted in our arms which can affect the readings from the sensor for up to 48 hours after the sensor is applied.
This is why it is common to insert a sensor a day before activating.

This is one of the oft mentioned limitations of CGMs. Yes, I mean all CGMs not just Libre.
If you are not aware of these limitations and so unable to take them into consideration, you could get very frustrated with the technology.

As for not knowing if you cause brain damage overnight, I think it is unlikely. People have celebrated 60 years with Type 1 diabetes. Most of those years were without CGMs or even finger prick meters.
I have had Type 1 for 20 years and only been using CGM in the last 4 years. Worrying about what damage I may or may not have done to myself in the first 16 years is not positive for my mental health. Likewise, worrying about the very occasional night when my CGM fails.
In fact, my body is pretty good at waking itself up when my levels get lower. CGMs are amazingly helpful but as they can fail, I believe it is very important not to lose hypo awareness.
 
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@RobertJ I have had similar overnight as well. I trust my glucose monitor over my CGM anyday. I find (like alot of people) that that CGMs tend to over report lows and highs and are most accurate only within range. Also the 4 is the floor is a guide set for those on insulin/glucose reducing medication. Those without diabetes can have levels in the high 3s and not be considered hypoglycemic.
 
Well, we are all different and I read a lot of people complaining of libre inaccuracies and unreliabilities.
It confuses me tbh.
I was on Libre 2 for 18 months and now libre 3 for 6 months.
L2 was 90% reliable and 90% accurate (knowing its limitations of course)
L3 is 99% reliable and 95% accurate.
L3 is so small, I am basically not aware it is attached to me!
Upper inside arm placement (with cover patch) which tends to avoid compression lows in bed.
Perhaps I am just lucky!
 
I agree.
I've used the Libre 2 for a few years now. I can't remember the last time a sensor failed. I use it for all my boluses and basal adjustments. And when checked against a finger prick (rarely) it's nearly always within 10%. The only thing it might miss is a rapidly falling BGs into hypo territory.
 
Hi all,

Glad to see all your comments, suggestions and other experiences.

To add to this, there is a freestyle support group on facebook for UK users with questions and issues. I believe there is currently a pinned post regarding a sudden influx of people experiencing the same issues over the last 3/4 weeks in terms of readings of 3.0 compared to finger pricks of 7/8/9/10/11 etc.

To update on my scenario, it took until Day 7 of my current sensor for it to become accurate (as in, how all my previous for the past 2 and a bit years have performed until the last 2 weeks) and was back within being spot on to 1.5 mmol out on readings. No idea why it's now suddenly working fine and as all my others until the last 3, or why it's taken 7 days to get to this point when mine have always been accurate within the first 24 hours or seemingly so in the past. But at least it's back to working and being accurate and not showing me as 3.2 when I was actually 9.2!

I'm due a sensor change in a few days... so I'll see how long the new one takes to bed in....
 

Exactly the same great experience as me, up until a week or so ago
 

100%.

In a way, I'm kind of glad it's happened as it has alerted me and promoted me to do more finger prick tests in the future, as you say, especially when low/high/questioning the reading as well as the odd random one to make sure it's working as expected!
/
 
Occasionally they go wildly odd on readings, but mostly pretty reliable once calibrated in xDrip to give more accurate readings.

Worth noting there is a period of 'insertion trauma' with new sensors, where sticking them in causes swelling around the sensor and stops it reading as accurate (true for all CGM). I insert a day before switching on to reduce the impact, obviously not possible if the sensor has failed though (then calibrating in xDrip needs doing every day or so for the first 2-3 days wearing)

Had a look at the Dexcom One, and not tried yet, but reviews I see are 'about the same' for accuracy etc, so not too bothered to change to them yet.

Running Libres (1 and 2) for about 5 years now and couldn't be without a CGM
 
Interesting. I've ben T1 for 57 years now and loved the Libre sensor when put on them a couple years back.
That was until they updated it recently to send the information without the need to scan, since then it all appears to have gone to pot.
Reasonably stable for years and then as soon as the new sensors appeared "erratic" doesn't even come close to describing it.
Somethings not right somewhere Libre.
 
I retired about 6 years ago and decided to spend some of my pension on a Dexcom G6. It was life changing but very expensive! So, when the Libre 2 became FOC I decided to switch and, of course, now it’s become a CGM, happy days. However, in the 9 months I’ve been using the Libre 2 I’ve had to return three sensors as they were giving inaccurate readings or just didn’t work at all. A couple of months ago I noticed a lady wearing a Dexcom G6 and I asked her if she was aware of the Libre 2. She said she had started using the Libre 2 but it was so inaccurate that her GP had prescribed her the Dexcom G6 free of charge! Has anyone else had a similar experience?
 
@ToxicWieper - no CGMs are free of charge. The tax payer has to fund the NHS. I appreciate they are available on prescription and if we have diabetes not treated by diet alone, we are exempt from paying.
However, considering anything from the NHS as free of charge is not the case.
Thank you for returning your faulty sensors to Abbott. For some thinking of them as "free" means they do not care to return them or wastes them in other ways. Especially when the NHS has little money to throw away.

<Sorry. I will stand down from my soap box now.>
 
Very interesting topic. I've used libŕe from the early days and have recently found them to be much more erratic (stopping early, not working after normal application, etc). I wonder if there is a production quality issue - demand must have shot up after they went on prescription. Of course, no-one could possibly comment...
I always take blood test kit when travelling and recently had to buy some contour strips in italy - much cheaper!
 

Thanks so much for sharing this @domoboy

I also appreciate the help Libre sensors have given me in managing my Type 2 diabetes I’ve been diagnosed with since 2008.



The data has helped me in my current journey towards remission. I’ve been using them (buying them) for about 4 years or so.



The last 3 months my sensors have been pretty flawless but last week I had the same symptoms as you. Sensor reading was 5.4 when started (accurate) then with minutes 3.6 and then “LOW” and then within 24 hours stopped working. The new one stopped working on the very first scan.



I think Abbott quality control needs looking at as I have a high sensor failure rate in the last year or so (then improved 3 months ago until recent failures).

When I return the failed sensors I never get the results of their analysis of the root cause.



For a Type 2 these sensors are super useful but honestly are a “nice to have”. I do worry about my Type 1 colleagues though that rely on the accuracy for their treatment…
 
Hi Jonathan
Sorry to hear that you will not be using the sensors anymore but if you have 3 maybe you could give them to someone else to use as they only have a short shelf life.
 
Hi, I'm a type 2 on insulin and meds and I have recently been put on the Freestyle Libre2 for my glucose monitoring.
I tend to have the opposite problem to a lot of you that have commented in that my levels tend to always be high. However, when I queried with my diabetic nurse regarding the differences in the readings of my sensor and my FP, I was told that it is normal because they measure different fluids.
The sensor measures interstitial fluid around muscle cells just under the skin whereas the FP measures capillary blood.
I was just advised that if my sensor alarm went off for high (over 18mmols) to do a FP.
Anyhow, I just thought I'd comment because no one on the thread had mentioned about the difference in the way the CGM works compared to finger pricking.
 
Hi

I regularly get woken up in the night by LibreLink (and Xdrip+) alarms telling me I'm low but a fingerprick test says I'm not. The apps may say 3.6 and the fingerprick
 
This happens to me a couple of times a year. I just use a stick test to cross compare every 15 min and if the error persists I always believe the stick test reading and change the sensor.
 
Wilsapp said:
Hi

I regularly get woken up in the night by LibreLink (and Xdrip+) alarms telling me I'm low but a fingerprick test says I'm not. The apps may say 3.6 and the fingerprick
Click to expand...
Sounds like compression lows. You may want to review where you place your sensor so you don't lie on it when you are asleep.
This is a known (and often described) problem with all CGMs. Libre users may experience it more often because it is only approved to wear on the arm.
 
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