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Libre 24hr activation

mountaintom said:
Is this official advice from Abbott? In that, you wait 24hrs before scanning?
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I don't think it's official as such.

But if you look at their data, the sensors generally become markedly more accurate (against a reference finger prick test) after a couple of days. I think it's on the info sheet that is shipped with the sensor.
 
Yes agree with urban, I still start using it after an hour but I also try not to take the readings so literally for the first 24 hours, there can be quite a marginally difference during this period.
 
I put on the new one and let it sit for the last 24 hours of the old one. Apart from a duff sensor that gave readings that ranged from -1.6 to +3.2 of my blood tester it seems to have worked well and reading have been settled from the time I activate. It’s worth one day of looking like a robot if the weather’s warm enough to go sleeveless.
 
Mine runs out lunchtime on a Thursday so the night before I give the skin for the new one a good exfoliate and apply it so it’s got around 18 hours to “soak” before I activate it. It’s pretty accurate from activation, then, gives time for the initial insult to the flesh of applying the sensor to die down. Also, the longer you’ve been using them, the more accurate they seem to become.
 
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The couple of times I have activated a sensor earlier than 24 hrs I have always found them irritatingly less accurate.

Mine seem to ‘bed in’ best on day 3.
 
Thanks guys. I put one on this morning (I’ve had 5 in my bathroom cupboard for months). I’ll try my hardest to leave activation til tmrw.
 
I think it's something which users figured out for themselves. It's supported by papers such as the one at the link below which mentions that the body needs a bit of time for the foreign body response and repair mechanisms to settle down, as they chew up glucose so give misleading results. Most of it is way too sciency for me to understand but it's worth a browse for those who are interested in what's going on behind the scenes with cgm.

If you look at the American version of libre, it has a 12 hour warm up period after activating. I'm pretty sure I read somewhere that they did that deliberately as they wanted the FDA to approve it for dosing, and FDA wanted a settling down period hardwired into it.


www.ncbi.nlm.nih.gov/pmc/articles/PMC2903977/
 
Well I waited the 24 hrs and activated it and it’s still reading 3 points higher at any given moment. So they ARE a waste of time for me.
 
mountaintom said:
Well I waited the 24 hrs and activated it and it’s still reading 3 points higher at any given moment. So they ARE a waste of time for me.
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I can live with the 3 points (sort of, though it's useless for hypos), but for me it varies from a more usual 3 points all the way up to 7 or 8 and occasionally (rarely) down to 1 or 2. If it was out by a consistent amount I could do the math to get a more realistic figure. OK, vent over. Am just wondering if I'd have the same issue with dexcom?
 
mountaintom said:
Well I waited the 24 hrs and activated it and it’s still reading 3 points higher at any given moment. So they ARE a waste of time for me.
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Mountaintom - I'm even more bonkers than the others in that 48 hours works best for me.

Annoying? Yes. Worth waiting? For me, also yes.

Abbott sometimes talk about "leaving it a few hours before activating, but there's nothing on their paperwork to that effect, unless I missed it going in.
 
As long as the readings are consistent and the difference between the blood sugar tests and libre remain the same then I can live with it too. It’s only difficult if I’m looking at trends on the graphs and bar charts. I did have one where the readings were all over the place but Abbott replaced it - sorry, unintentional very bad pun.
 
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