Freestyle Libre

rowlyc

Member
Messages
12
Type of diabetes
Type 1
Treatment type
Insulin
Dislikes
running
I'm a new user of Freestyle Libre, only on my second sensor.
I know that it has a lag time and that both the libre and finger pricking is never going to be 100% correct. And that you should always trust finger pricking to be more accurate than the libre.

Taking all this into consideration, has anyone else experienced the libre reading low 3.4, me feeling low, but finger pricking showing 5.2?
This has happened twice recently and really puzzles me. I spoke to DSNs about it and I think she thought I was making it up, the only thing she said to explain it would be if maybe my hands weren't clean whilst blood testing. But it has happened again now, so I sincerely doubt this will be the case twice, especially how much I'm washing my hands lately!
Any suggestions greatly appreciated.
 

Antje77

Oracle
Retired Moderator
Messages
19,284
Type of diabetes
LADA
Treatment type
Insulin
Taking all this into consideration, has anyone else experienced the libre reading low 3.4, me feeling low, but finger pricking showing 5.2?
Have you been running higher levels lately? If so, it could've been a false hypo at 5.2.
 

rowlyc

Member
Messages
12
Type of diabetes
Type 1
Treatment type
Insulin
Dislikes
running
Have you been running higher levels lately? If so, it could've been a false hypo at 5.2.
Not particularly, my highest numbers are usually only 12ish, but that's only if I'm going to exercise or until I notice and then I would correct.
And I felt hypo also.
 

Antje77

Oracle
Retired Moderator
Messages
19,284
Type of diabetes
LADA
Treatment type
Insulin
And I felt hypo also.
A false hypo is when you've been running higher numbers for a while and you start to feel hypo at above hypo levels. Like when you've been above 8 all the time for some time you can well feel hypo at 5.5.

Libre is known to read lower than blood for some, so I thought perhaps this would be the case for you: Libre reading too low, blood being above 5 but still feeling hypo because your body isn't used to being in the 5's.

Looks like this is not the case though if your numbers have been ok lately.
Have you tried a new tub of test strips in case they've somehow gotten compromised?
 
  • Like
Reactions: rowlyc

KK123

Well-Known Member
Messages
3,967
Type of diabetes
Type 1
Treatment type
Insulin
I'm a new user of Freestyle Libre, only on my second sensor.
I know that it has a lag time and that both the libre and finger pricking is never going to be 100% correct. And that you should always trust finger pricking to be more accurate than the libre.

Taking all this into consideration, has anyone else experienced the libre reading low 3.4, me feeling low, but finger pricking showing 5.2?
This has happened twice recently and really puzzles me. I spoke to DSNs about it and I think she thought I was making it up, the only thing she said to explain it would be if maybe my hands weren't clean whilst blood testing. But it has happened again now, so I sincerely doubt this will be the case twice, especially how much I'm washing my hands lately!
Any suggestions greatly appreciated.

In a word, yes. It happens often. The libre is around 10/15 minutes behind a blood test, so if my libre shows 3.4 ish (which it often does), I sort of know that it was at that level 15 minutes ago....BUT it is not entirely accurate on readings below 4 so really I can only guess at the true level 15 minutes ago. When I check this with a blood test real time, it usually shows a good 2mmol higher but of course that is the reading 'now' when I do the finger prick. With me so far?? With the feeling low, when I feel low I know by experience that I am going to be in the low 4s, so a finger prick test showing 5.1 may be out because they are not particularly accurate. It is confusing I know. I rely on the way I feel and a combination of the libre and a finger prick test and experience. If for example I am getting shaky and a test shows in the 4s or sometimes a 5, I treat it as a hypo by having a very small snack or a bigger snack if it's even lower! Also even if the libre was accurate at 3.4....that was 15 minutes ago and my body often gives itself a telling off and releases its own glucose supply, thus by the time I do the test it's back to normal even though 15 mins previously it was low! x
 
  • Like
Reactions: rowlyc

Bob Falfa

Active Member
Messages
25
I had the Libre for a very short time( I had a reaction to the glue )
I admit I was less than keen of the System, the principal is fine , the application not so.
initially I was using TrueYou , to double check reading , I found the same as others are saying.
I would have like to the projection function in action, but still
I note results on a spreadsheet
If I get the same result at the same time but different day, I use One of a selection of older meters I have ( and still have test strips for that work)......It does as a double check
A bit like KK123 above , just different meters

I suppose I must be old school, I started with having little faith in Abbott, that has not changed.
I'm probably one of very very few
 

UK T1

Well-Known Member
Messages
334
Type of diabetes
Type 1
Treatment type
Insulin
I think I've been fortunate with my libre sensors so far, but have loved having it! It is worth remembering (as said above) that all sensors and all finger prick/capillary glucose monitors can be off. So in theory the sensor could have been at the bottom of its error range while your meter maybe was at the top of its error range? I think that's what was suggested above.

It also of course if possible that you were a bit lower and released glycogen/glucose to bring it back up. When my sensor and meter don't correlate I set an alarm to scan 5/10/15 mins after I've tested to try and see for my own peace of mind whether they do now agree a bit better. Of course a new sensor and a new batch of glucose testing strips will have a different tolerance and so possibly different readings, which doesn't make this easy!

It does always surprise me how quickly my warning symptoms can kick in at different thresholds. Eg one week I'll feel awful if my bloods are at 8/9, but if I let them stay there it only takes a few days for my body to assume this is the new norm and feel fine at those levels, and suddenly feel hypo-ey (technical term ;) ) at 5ish.

Has it only happened twice? Same sensor/batch of strips?
 

Lucieni

Member
Messages
7
Type of diabetes
Type 1
Treatment type
Insulin
I’m new to freestyle and had a 3.4 and plummeting reading today, felt fine and finger pricked at 5.6.
 

Lucieni

Member
Messages
7
Type of diabetes
Type 1
Treatment type
Insulin
How often are you all scanning? At the moment (2nd day) I’m experimenting with once an hour but plan to mirror my finger pricking.
 

Antje77

Oracle
Retired Moderator
Messages
19,284
Type of diabetes
LADA
Treatment type
Insulin
How often are you all scanning? At the moment (2nd day) I’m experimenting with once an hour but plan to mirror my finger pricking.
Apparently 31 times a day on average over the last 3 months, plus a couple of fingerpricks every day. I've been using the Libre for over 3 years now.

95260460_10220577149613047_8970062021152210944_o.jpg
 

KesLouise

Well-Known Member
Messages
85
Type of diabetes
LADA
Treatment type
Insulin
I’m on my first sensor, how often should I finger prick test or is it just when showing particularly high or low?
 

Antje77

Oracle
Retired Moderator
Messages
19,284
Type of diabetes
LADA
Treatment type
Insulin
I’m on my first sensor, how often should I finger prick test or is it just when showing particularly high or low?
That's up to you and your consultant. Some hardly ever do a fingerprick test, others double check every day.
 
  • Like
Reactions: KesLouise

UK T1

Well-Known Member
Messages
334
Type of diabetes
Type 1
Treatment type
Insulin
I’m on my first sensor, how often should I finger prick test or is it just when showing particularly high or low?

I was told (at the Libre training):
- When the libre shows below 4
- When the libre shows above 13
- When my symptoms don't match what the libre says.

We know the libre is least accurate at very low and very high glucose levels (hence first 2 suggestions) and also that it lags behind your actual glucose level, so there was the tentative advice to do a finger prick when the arrow is straight up or straight down before doing any remedial action eg insulin corrections. Sometimes the straight up or straight down arrow is understandable so I don't finger prick just because it's there (eg if I've eaten within the half hour and it says its going up, but scan so I can drive).

We also know errors can occur so if the symptoms don't match your libre it is good to have a back up. There will be error margins with all devices (including finger prick devices) which is worth remembering.

I hope you enjoy it! I've loved having mine and it has helped me reduce spikes around eating in particular. The ability to use it to help pattern regulation is fantastic in my opinion!
 

KesLouise

Well-Known Member
Messages
85
Type of diabetes
LADA
Treatment type
Insulin
That's up to you and your consultant. Some hardly ever do a fingerprick test, others double check every day.

I mean that’s great but I haven’t seen and am unlikely to see a consultant any time soon :( also self funding until able to
 

KesLouise

Well-Known Member
Messages
85
Type of diabetes
LADA
Treatment type
Insulin
I was told (at the Libre training):
- When the libre shows below 4
- When the libre shows above 13
- When my symptoms don't match what the libre says.

We know the libre is least accurate at very low and very high glucose levels (hence first 2 suggestions) and also that it lags behind your actual glucose level, so there was the tentative advice to do a finger prick when the arrow is straight up or straight down before doing any remedial action eg insulin corrections. Sometimes the straight up or straight down arrow is understandable so I don't finger prick just because it's there (eg if I've eaten within the half hour and it says its going up, but scan so I can drive).

We also know errors can occur so if the symptoms don't match your libre it is good to have a back up. There will be error margins with all devices (including finger prick devices) which is worth remembering.

I hope you enjoy it! I've loved having mine and it has helped me reduce spikes around eating in particular. The ability to use it to help pattern regulation is fantastic in my opinion!

Thanks will definitely keep this in mind.

Finding it really useful!
 
  • Like
Reactions: UK T1

Antje77

Oracle
Retired Moderator
Messages
19,284
Type of diabetes
LADA
Treatment type
Insulin
I mean that’s great but I haven’t seen and am unlikely to see a consultant any time soon :( also self funding until able to
Ah, in that case you'll have to find your own way. Same as I did when self funding :)
I think it mostly depends on how much work you want to put into diabetes and how much you hate fingerpricks. If you don't mind double checking, why not do so regularly for a while to develop a 'feel' for the quirks of the device? And I second testing below or slightly above 4, with high numbers and whenever something seems off.
Enjoy your Libre!
 
  • Like
Reactions: KesLouise