Freestyle libre readings inaccurate

[Natalie123]

Hi all. In using a freestyle libre and have noticed that my readings are very different to my finger prick tests. This wasn't the case before! For example, this morning my libre said I was 2.4 and my finger prick meter said 7.8. just now I got a lo on my libre and 4.8 on my finger prick one. My libre meter is quite old and I do have a newer one so I might try that. Do I need to start a new sensor or can I switch meter without changing the sensor? Any info would be much appreciated. I don't want to bother my diabetes team at this busy time!

 

[Sally71]

It would suggest that the sensor isn’t working properly if it's continually reading low when you aren’t! How long have you had the sensor in though, sometimes they take a few hours to settle if you've only just put them in. If it doesn’t sort itself out by the end of the day then you probably need a new one. Abbott are pretty good at replacing faulty sensors though, as long as you phone them and don’t try to email them, they don’t seem very good at answering emails!

Unfortunately if you want to switch to a different reader you will have to start a new sensor also, only the reader which initiated the sensor can read it afterwards. The exception being if you use the Libre app on your phone then you are able to switch between reader and phone if you start them up in the right sequence.

 

[JohnWhi]

I have experienced quite a few times the divergence you quote between the Libre interstitial glucose reading and the blood glucose test. Once during the night, when I woke feeling low, the Libre read "LO" but the BG test, before taking action to correct, read 6.8mmol. They are not measuring the same thing and, for example, if you correct a hypo, blood sugar will rise much more quickly than the Libre reading. Having said that, and having used the Libre for a few years, I find they are nearly identical most of the time if one is in the normal range. In my overnight episode, the Libre was actually giving an accurate measurement of how I felt!

 

[mikeyB]

If your Libre meter is quite old, it won’t have the latest software and algorithms, so won’t be accurate. If your other meter is less than a year old it should have the new software on board. Either that, or update your reader from the Abbott website.

 

[Bruce Stephens]

Do I need to start a new sensor or can I switch meter without changing the sensor?

Might be worth contacting Abbott and seeing if they can say. If the readers differ in the version (if you hadn't updated the first one, say) then that definitely won't work (after changing the firmware you have to use a new sensor). It's possible to use both a reader and the phone app without any problems, but to do that you have to initialise the sensor with the reader (suggesting there might be some problem in connecting a reader to an already initialised sensor). So I think probably you'd have to start a new sensor, but Abbott are the only people who might know for sure (and if you ask about this maybe they'll offer you a spare sensor, so it might be worth asking anyway).

Quite a few people report sensor readings drifting downwards. It's not something I've had. I wonder if for some people some sensors gradually work themselves loose (so the probe bit slides out) or something like that?

 

[Natalie123]

Hi, thanks for you help. I think it's a faulty sensor. It just gives a flat line and says lo constantly. I'm definitely not low! Unfortunately I don't have another sensor so I'll have to wait until Monday for my prescription probably.

 

[grovesy]

Hi, thanks for you help. I think it's a faulty sensor. It just gives a flat line and says lo constantly. I'm definitely not low! Unfortunately I don't have another sensor so I'll have to wait until Monday for my prescription probably.

You should still contact Abbott.

 

[Kaylz]

Hi, thanks for you help. I think it's a faulty sensor. It just gives a flat line and says lo constantly. I'm definitely not low! Unfortunately I don't have another sensor so I'll have to wait until Monday for my prescription probably.

Definetely report it to Abbott and they will more than likely replace it xx

 

[SB2015]

Hi, thanks for you help. I think it's a faulty sensor. It just gives a flat line and says lo constantly. I'm definitely not low! Unfortunately I don't have another sensor so I'll have to wait until Monday for my prescription probably.

Your readings certainly sound like a faulty sensor. Although the reader may be an older one it still shouldn’t give such readings. It is still worth reporting this to Abbott, who are very likely to send out a replacement.