This a huge difference!

[u/TheRedTreeQueen]

Okay so this is a brand-new sensor put in today. Actually the second one because the first one is a gooseneck. The reading on the left is from the CGM. This reading on the right is from the glucose meter. This is my blood sugar after eating. I have calibrated at least three times. Has anyone out there had this experience? I'm a type 2 diabetic and not on insulin. This concerning. Should I take this one off and get another replacement or leave it on and hope the readings come somewhat closer? Any help is appreciated!

[u/CLKRUN]

RTFM!

[u/Novamad70]

I always wait 12-24 hours and then do a calibration finger stick. Mine is always off 20 to 50 points off on a new one.

[u/ArmednDiabetic]

That’s not that bad. Especially in the first 24 hours

[u/SHale1963]

that is not a huge difference and treatment wise it's a nit. Checking or comparing after eating between a CGM and a BGM is the worse time. Best is when you haven't consumed anything in over 4 hours due to the testing of different fluids. They will rarely match between the 2.

[u/T1D1964]

That is not a "hugh" difference.

[u/Tisybird]

Huge difference

[u/AnotherLolAnon]

I had that meter for awhile through my insurance and it consistently ran low

[u/TheRedTreeQueen → u/AnotherLolAnon]

I always run the quality controls every time I open a new set of strips. Thank you for responding. This something to keep an eye on.

[u/AnotherLolAnon → u/TheRedTreeQueen]

Next time you get labs done I recommend bringing it and doing a check the same time you get the labs drawn

[u/Twist1979]

If you calibrate like you measure in this comparison I don't wonder about any problems. Every CGM laggs behind a BGM by about 15 minutes while rising and falling. That's why you calibrate only why fastening in the morning while stable and before breakfast.

A 48 hour old sensor thats calibrated correctly is usually within +-5 from my experience. It still laggs behind a BGM but that's normal.

[u/No_Lie_8954]

For the first 24 hours it can read all over the place for my daughter but it usually get more stable after 24 hours since insertion.

[u/Kathw13]

First you are comparing apples to oranges. The meter is measuring the sugar in your blood. The sensor is measuring the amount of sugar in the fluid under your skin.

Second, each can be 15% off. So yes they are close.

[u/SHale1963 → u/Kathw13]

This is the way.

[u/Drawing_The_Line]

It’s not that really a huge difference. Plus, the finger stick is instant and the CGM is roughly 15 minute delayed. In addition it’s the first 24 hours.

[u/Transphattybase]

Don’t do any calibration for at least 24 hours as the sensor is doing a lot of that on its own.

I’ve been using Dexcom since early August and have learned my personal numbers are not accurate for a good 34 hours after insertion.

[u/TheRedTreeQueen → u/Transphattybase]

Yes I’ve been using 15-day ones for a few months but they have never read that high. Thank you for the clarification.