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Finger prick variances

A

ABREY

Newbie
Messages
1
Type of diabetes
Type 2
Treatment type
Tablets (oral)
Hello,
I've had a CGM for about 10 months. After the initial 3 months I had my A1C tested (50 down from 58). Recently I've had more highs and lows, haven't been eating properly or had sensor in 100% of the time etc. I'm attempting to get the boat turned back in the right direction again but it's proving difficult. (The dawn phenom i have been experiencing is 8 to 10 mmol/l every morning for a few hours - for years. Main reason my A1c isn't lower. Any advice?? I'm on full whack of metformin only) My current CGM is reading quite low for the last week and I've tried finger prick to confirm, however I'm getting 3 wildly different reads for one prick! Not to mention its 1.5mmol to 2mmol higher than CGM most times. I just pricked my finger and got 1st drop: 7.8, 2nd drop 9.4, 3rd drop 8.5. Help!
 
Blood test machines have to be with 15% of the actual blood glucose level to be considered accurate, so getting slightly different numbers is not unexpected I'm afraid
7.8,8.5 and 9.4 are all with 15% of 8.5 so its probably somewhere around there)

Some times the CGM's can be a little out, which is why checking with a blood test every so often can help
eg. when I was back on the Libre 1 it always showed about 1mmol/L lower than I was but I knew that so knew what it was, it did seem to be a constant difference for me at least (edited out the stuff I seemed to say twice)
 
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the variation are common well for me anyway, especially first thing in morn so you are not alone there. I only use a blood monitor so have ni experience with a cgm
 
ABREY said:
Hello,
I've had a CGM for about 10 months. After the initial 3 months I had my A1C tested (50 down from 58). Recently I've had more highs and lows, haven't been eating properly or had sensor in 100% of the time etc. I'm attempting to get the boat turned back in the right direction again but it's proving difficult. (The dawn phenom i have been experiencing is 8 to 10 mmol/l every morning for a few hours - for years. Main reason my A1c isn't lower. Any advice?? I'm on full whack of metformin only) My current CGM is reading quite low for the last week and I've tried finger prick to confirm, however I'm getting 3 wildly different reads for one prick! Not to mention it’s 1.5mmol to 2mmol higher than CGM most times. I just pricked my finger and got 1st drop: 7.8, 2nd drop 9.4, 3rd drop 8.5. Help!
Click to expand...
CGM’s read the glucose in the interstitial fluid. Fingerpicking reads the glucose level in your blood. So these devices test glucose amounts from two differences sources in your body. Interstitial readings usually lag behind actual blood readings by up to 15 mins depending on the individual. Then you have the allowable error 15+/- for both devices.

As for different readings, one after the other, fingerpicking , blood sugars are in constant flux, they are never static. Variables are at play, energy usage , stress levels , liver input , insulin signalling, hormone adjustments , residue food in the stomach, the digestive process in your gut, to name a few. Your body is constantly adjusting, it’s a finely tuned machine, always compensating, always adjusting every moment of the day.

Ed to add insulin
 
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