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Freestyle Libre very inaccurate??

MissZButler

Member
Messages
17
Location
Cumbria
Type of diabetes
Type 1
Treatment type
Insulin
Dislikes
When my blood sugars don't behave!
Hi everyone,
I'm new to using the Freestyle Libre - and was diagnosed with T1DM in February.
I've been finding that the libre has been really off in comparison to my finger prick readings - especially at night time before bed. For example tonight my Libre is reading 3.8, but I do not feel as though I am having a hypo and I have really good hypo awareness usually. When I've done my finger prick it is say 7.2.
It can cause quite a bit of anxiety as I don't want to go to bed worrying my reading are low - but been waking up in the night to check with the finger prick and have not had night hypos.

Does anyone else have these issues? Thinking of coming off my libre as it seems to be not very helpful in terms of getting accurate readings.
Thanks in advance
 
Iv not long started on the libre. On my third patch now and Iv not had any issues like you have. Maybe it's the sensor and you need it replacing? Possibly ring Freestyle and speak to them about it?

I know readings can be a little different as the time delay on them can be 15 mins

I generally find my reading arent far off at all thankfully and with my work and sport I do it's a great thing to use
 
Is this your first sensor?

There are duds every now and then. Sometimes it also comes more closely into line after 24hrs or so.

Some people wear them for 24hrs before activating them to allow them to ' settle in'.
 
urbanracer said:
Is this your first sensor?

There are duds every now and then. Sometimes it also comes more closely into line after 24hrs or so.

Some people wear them for 24hrs before activating them to allow them to ' settle in'.
Click to expand...
This one is my 3rd sensor now - the first worked well but the last two I've had the inaccuracies with them. I have it with the app on my phone and its so handy but with it being so out (by -4mmols sometimes) I'm just very cautious that I don't want to rely on it too much.
Yeah I have read about that and I activated this one 24hrs after too
 
I'm going to keep the faith with it - I'm wondering if it is the 10 minute delay...but then I wonder surely my BM is not swinging by as much as the Libre is saying...
I might keep a close record tomorrow of both libre and finger prick readings and do a close comparison and try and think what might be causing it (like active days, carb intake, stress etc)
 
Do several fingerprick tests and record the libre result 10 to 15 minutes later. If you are getting a large discrepency you can ring abbott and they will probably send you a new sensor (don't chuck the old one out as they may want it back).

If your results are consistently out by the same amount you may benefit from the xdrip app, which allows you to calibrate the sensor results against your blood sugar readings.

Some (luckily not many) people's bodies just don't agree with the libre and they never get good results. I'm unfortunately in that category and had to go back to fingerpricks after 8 months of libre use. (I became allergic to the sensor and the results when haywire).
 
I found, if its any help, that I have gotten to learn libre. It usually reads lower for me, too. I now don't use it for dosing, but it is still invaluable for learning trends, and that arrow usually doesn't lie.
 
geekypants said:
I found, if its any help, that I have gotten to learn libre. It usually reads lower for me, too. I now don't use it for dosing, but it is still invaluable for learning trends, and that arrow usually doesn't lie.
Click to expand...

Hi geeky, when I first went onto the Libre I wasn't sure whether we were supposed to use it to dose with but am told the answer is yes, and that is why they are now only providing 50 test strips 'every 2 months or so', that equates to 1 a day or thereabouts. So now I use it in conjunction with my insulin dose but obviously have to calculate the fact that it lags behind blood tests and is not massively accurate when it gets into the lowish 4s which I am often in. I do love the freedom of it and being able to monitor trends but I will admit I have a concern about whether it is accurate enough to dose insulin. x
 
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Hi,

I’ve had the exact same problem this morning with a new sensor I applied yesterday. It was inaccurate from the get go but I stuck with it for 24 hours. It was about 5mmol lower than blood reading and had actually registered a “low episode” this morning when in actual fact I wasn’t having a hypo at all and was 9.0 on my blood meter.
Anyway, I phoned Abbott and they are sending me a new sensor.
Most of my sensors have been accurate, the odd one has started dodgy, but fallen in line after 24 hours. My top tip is to take photo of freestyle meter reading next to blood reading or screen print and photo of blood meter. When you ring them about it they ask for 3 specific examples so at least you have the proof they need. I’ve always found them to do the right thing and agree to replace. I’ve been on libre since October and I’ve had 2 inaccurate ones.

Hope this helps.
 

I've been told no for dosing, especially with pump microdosing. Mad how much variance there is in different areas!
 
I went through 4 of these sensors and every one started giving false very low readings followed by a constant "lo" message after a couple of days. Contrary to what other people are saying, mine all started off working well and got worse after 24 hours. Perhaps some people reject them. I cannot see how I could have got 4 duds in a row. Anyway I've given up and gone back to regular fingerpricks. It was too much anxiety and not worth the hassle. The technology is constantly improving so hopefully there will be something more reliable and freely available soon.
 


I find the same, annoyingly it does skew the stats. My last hb1ac was a lower level than the 90 day libre reading.

I think I need to stop being obsessed, use it as a tool and get on with living.
 
I have been using the FreeStyle Libre since May 2019, when I was diagnosed T1 at age 71, after being (mis)diagnosed with T2 at 69. I really love it and I keep the monitor beside my bed because after first being diagnosed and trying to absorb all the information, I was having a lot of lows overnight. If I get a reading that I think is wrong, then I finger prick just to make sure. They have been very consistent. A couple of months ago it was getting weird. My DE gave me a new monitor, however the sensor was no good after it had been used. I called Abbot and the gentleman explained to me what sometimes happens with the sensors. He then sent me a new sensor to replace the other one. He told me to keep both monitors so I'd have a spare. I got good service and I'm satisfied with it. Now if I could accept that I have T1, I might be able to handle my emotions a lot better. Stay safe and stay healthy, everyone.
 
I’ve seen that this post is a few months old but I still wanted to make a comment.

The Freestyle Libre has unfortunately been very inaccurate for me and it has frustrated me. Imagine spending £100 a month for a thing that doesn’t work? Out of 5-6 sensors only 1-2 have been relatively accurate. I’ve experienced different problems with different sensors— some of them incorrect by about 2.5-3.5 from the start, others accurate for 10 days then becoming off by 4 after that, while others work for 10-11 days then suddenly ceases functioning.

I’m looking to try the Dexcom G6 but at a price of £159 seems unlikely that I could fund that in the long term (you could get the latest iPhone every year with that money).

For me the only options seem to be Dexcom G6 or finger pricking. I’m not even sure if the G6 will work either but will have to try
 
TypeZero. said:
For me the only options seem to be Dexcom G6 or finger pricking. I’m not even sure if the G6 will work either but will have to try
Click to expand...

I had to stop using the libre after 8 months because I became allergic and (as a result?) the readings became completely inaccurate, wildly low and/or high compared to finger pricking. So I went back to finger prick testing (retried a libre every year to see if it would work but it never did), using 50 strips a week.

2 months ago I decided to try out the G6 (wasn't prepared to buy an older phone to use the G5 which was all that was available in NZ before that) and so far it's been fantastic. Of course, there's a significant chance I'll eventually become allergic, and have to go back to finger pricks, but till then I'm making the most of the G6.

The glucomen day that you posted about earlier looks potentially like a G6 equivalent (more environmentally sound though you do have to do some finger pricking). Maybe try out their trial kit?

I don't think any cgm replaces a meter completely, if you're hypo you need to blood test, but its ability to forestall hypos is awesome.

Good luck.
 

If my body doesn’t accept it then there’s nothing I can really do. Will have to try the Dexcom G6 or Glucomen Day CGM though. It’s encouraging to hear it has worked for you. If it is life changing then I will definitely find ways of funding it especially since I’m looking to get a pump in 6 months or so and I’ve heard of ways of looping CGMs and pumps obviously I would never trust a Libre to receive automatic insulin therapy but Dexcom has been approved
 
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