Freestyle Libre Sensor

[Cowgirl_232]

Hello, I have just bought the sensors for the Freestyle Libre after being on them for 2 weeks last year and not getting on with it I wanted to give them another go.
I find that my levels differ so much from my finger prick blood tester , has anyone else found this and does anyone have any good or bad points for it?

Thanks 🙂

 

[Bruce Stephens]

I find that my levels differ so much from my finger prick blood tester , has anyone else found this and does anyone have any good or bad points for it?

I find (after maybe a few hours, initially) readings are generally within 20% of my glucometer (which itself has some inaccuracy, presumably), so (when I'm 4-7 mmol/L) it's good enough. And outside that I can tell I'm too low or too high, which is also good enough for basic action.

Agreed it's not a general replacement for a glucometer and test strips. Even if it's way out for you (and for some people it is) you may get some value from seeing the shapes of the graphs, and from what that says for direction when you're testing with a strip. (If your strip says 8 before you eat, knowing whether that's 8 dropping like a stone vs rocketing is valuable, even if the value the Libre's giving is hopelessly out.)

It's also possible it just doesn't work for you, for some reason.

 

[Ljc]

Hello, I have just bought the sensors for the Freestyle Libre after being on them for 2 weeks last year and not getting on with it I wanted to give them another go.
I find that my levels differ so much from my finger prick blood tester , has anyone else found this and does anyone have any good or bad points for it?

Thanks 🙂

Hi @Cowgirl_232 , welcome to the forum.
How big is the difference between meter and scan

Just a few thoughts, apologies if you already know.
Their is a 10+ minute lag between glucose in the blood and the glucose in the interstitial (sp?) fluid that the sensor samples , do you do a blood test then after say 10-15 minutes scan .

I find my sensors are more accurate if I apply them but don’t activate them for around 24hrs. It seems to give time for any inflammation caused by piercing etc to settle down

If your sensors are well out, phone Abbott, they will advise and replace sensor but you need to send the faulty one back , I believe they send a pack for you to do this.

 

[khskel]

I tend to look at the relative rather than the absolute figures and when I'm libred up I can restrict finger pricking to driving and hypo or near hypo events.

The main benefits I have found are getting my basal level pretty good and ironing out post meal peaks and troughs to an appreciable extent.

 

[christophe]

Same as the above.. I don't find I rely on the figure too much, and I do a finger jab to verify or disprove a reading if I am that worried by it. The graph is hugely informative though.. gets the basal setting just right and checking for rise/fall after injecting or eating shows how fast and then how much the insulin or food (or exercise,stress, weather.. laziness.. whatever) affects you. It's the closest thing to a window to your bloodstream. If you can work with it it's a great help.

 

[SB2015]

All of the abov and ...
I know that the sensor readings are closer to BG readings if I am well hydrated. If I am finding thatbthere are bigger deifferences I use it as a reminder to drink some water.

Apart from that it is the patterns shown on the graphs and the direction of travel arrow that I focus on, reverting to blood test if things are going very low and if too high, so needing to do a correction on my pump

 

[Radders]

I have phoned up about two sensors in the past year that were out by a large margin. The first time I was told that if you get three readings more than 15% out the Sensor is faulty. The second time I was told that they wanted the comparison blood readings to be done on their meter. I said that I don’t have strips for their meter and after I explained how difficult it would be to persuade my GP to prescribe two different strips (I have tried this and one type gets removed, or they prescribe the wrong one...) Abbott sent me 10 boxes of 10 strips! On both occasions the sensor was replaced free of charge and I had to send the faulty one back.
I also wait roughly 24 hours before activating since noticing very erratic results when I didn’t.
I usually find that their meter agrees with my meter when I’ve had cause to check. Sooner or later the strips will reach their expiry date and I’ll be back to square one!

 

[mikeyB]

I’m a constant Libre user, and I’ve never had a faulty sensor. And I never wait 24 hours to activate sensors either. I’ve given up checking the readings, because they never differ from fingerprick tests by more than the usual variability you get between normal testing strips. The only exception is after correcting a hypo, when the catch-up is too slow.

You have to remember that none of these systems are truly accurate. And as SB2015 says, being well hydrated helps with the Libre.

 

[Barbie1]

I never wait 24 hours to activate
Nor do I check every test with real blood

But what I have found is that within the acceptable (or target) range of 4 - 8, the Libre is close enough. Outside of that range I find it unreliable and usually discount it and do a proper test if I need to know that closely. Which is not always the case, because I am a very bad diabetic.

But I do value the trend indicator and will take appropriate action if rapid movement, up or down, is indicated