Dexcom BG's are waaaaayyyyy off

I just tested my BG twice and I was 110 and 114. The problem is my Dexcom said I was 210. Has anyone dealt with this problem before? It’s like my Dexcom stopped being accurate the last 3 weeks (3 sensors).

I have had issues with Dex saying I was high (250’s) and I was actually low (below 60) but only twice and with the same sensor. Does the dex’s numbers change when you input a correct bg reading?

There’s lots of good discussion about when it’s best to calibrate the Dexcom with actual BG readings on this site. Search around and you’ll find plenty of good reading material that should help.

I’ve had that happen as well but with one sensor, not with multiple ones.

You should call them.

Are you dehydrated? That can throw the Dex off also.

Very common problem, Kevin. I have had readings that far off manhy many times, we have to remember, this is a relatively new technology. Frustrating, I know. I wuld give Dexcom a call and see if they ahve any suggestions. You havent been taking Tylenol in the past few days, have you? I ask because Acetaminophin (sp?) (which is the active ingrediant in Tylenol, as well as MANY other medications) will throw the dex WAAAAY off!

No Tylenol. The problem is that the Dexcom was super accurate and all of a sudden it isn’t and now I’m having to test more to make sure. sucks

it does update when I put in the correct BG’s. it makes me do it twice when it is way off.

Last summer, I think they replaced 5 sensors out of 2 boxes that seemed to be bad.

Yep… it happens to me…

Reality is that any CGM is not 100% reliable… and it’s never going to be. My experience with Dexcom is that often you’ll get a batch of sensors that just doesn’t read very well, despite the fact that most of them do.

Had a similar problem just yesterday, with a new sensor. The initial calibration seemed OK but the numbers were consistently off both on the low and on the high side.

I simply stopped the sensor well after a meal, and recalibrated it as if it was new, and things are now back to normal.

Maybe your calibration did not come out OK, you always have to calibrate in times in which the BG is fairly steady, if possibile.

funny this happened to you at the exact time it happened to me. My dex says 220 and I am 138 on meter. I have worn 3 days and its been doing this crazy reads since day 1. I have it in my thigh. Wonder if that makes a difference. I will rip it out if it does not get better by tomorrow.

Sounds like others have better advice.

So you hit “stop sensor” and start it like it was new?

Yup, exactly. And after the two hours for the new calibration, the sensor started to play nice again. Happened like this only another one time in the two years I’ve been using the Dexcom.

yeah, it really sucks when you get a sensor that isn’t accurate. Then, like you, I find myself testing all the time like crazy cuz i never trust it.

For me, I’m beginning to wonder if it is site related. I have a couple spots about half way between my belly button and love handles that seem to be pretty accurate, but if i get too far away from them on either side, it seems like i get less accuracy.

Not really sure, just feels that way.

Also, ti sounds like you may change it every week, as suggested? I sometimes find my sensor gets more accurate the longer i leave it in. Second week is usually better. Although a good sensor will normally settle in to being accurate by the 2nd or 3rd day.

I have been having differences too. I am currently on antibiotics, so I attribute part or most of my problem to them.

I have had the same problem. Please make sure to document the #s. I contacted Dexcom because I had other problems as well and they replaced the whole system.

Some thoughts:

Sensor placement can be a bear. On my gut had results you mention.

I use top of arm outside and usually get good results.
Ocaasionaly I get sensor that is useless - or location is poor and have to load new sensor
on different arm. It happens too many times.