Dexcom "stuck" at certain readings

I'm getting only minor fluctuations and I know my BG is changing more than the Dexcon indicates. About 60 hours ago, it was "stuck" in the 50s and 60s overnight and throughout the morning. It varied maybe 10 points at the most with a constant flat arrow. I'd try to recalibrate but the Dexcom wouldn't respond. When it did, it would "stick" at the calibrated BG.

Over one stretch, my BG was 98 before hitting the gym, and the Dex was in sync. I took a carb load, which would normally send me into the 140s, that barely registered on the Dex. After my run, my BG was in the 60s and the Dex was still reading 108 and stayed there for over an hour, with a straight arrow, until I recalibrated down to compensate. It then got stuck there through my post lunch BG change.

The sensor had been in10 days but, otherwise, seemed fine. No ???s or unusal signal disruption. I put a new sensor in last night, but it's doing the same thing. I've watched my post breakfaast BG go from the 70s into the 140s before my workout, but my Dex says shows 79 with a slight up arrow.

Anybody ever had thi happen?

This is usually what happens when I have “old” sensor that is past it’s prime… usually it doesn’t happen at only 10 days though… we’re talking 20+. The graphs just get very “flat” and tend to slowly trend up or down from where you really are.

Maybe the transmitter, or receiver, is nearing the time it needs to be replaced? They don’t usually go much beyond a year . I think that is correct.

i’m not sure if this is relevant to your situation, but i notice that Dex does get stuck when i am dehydrated. perhaps there is less interstitial fluid and it is more stagnant? this is the best guess i have. dex’s accuracy (especially during times of quick change) seems to improve when i drink more fluids.

I’ll keep this in mind Richard. I just gor my Dex this past June, so hopefully neither one is dying yet. Thanks!

Hmm, this is a possibilty. I can be terrible when it comes to hydrating, especially after a workout. Thanks!

The Last time I did two weeks, I got much more accurate numbers the second week. This time was the same until Thursday. I was traveling back from the Caribbean to New York.

The numbers kept going up for no apparent reason, I kept giving myself correction boluses.

Finally I realized something is wrong, when at 233 and still rising, I tested with my meter, and lo and behold, it is 87. I test with a different meter at 10:30 at night, and it is 72. I enter both in the receiver and it corrects itself. Then I woke up at 6:30 To the low alarm that had been going on all night, and I see that the whole night, the receiver has 39 for every reading. I was sure it was not correct, and my two meter readings both at 93 proved it. The receiver corrected after the BG entry and kept close to the new calibration.

Friday, The Dex kept at the same levels for hours, moving very little even when I ate.

What made it do this unusual behavior is not clear to me. Is it because i am on the second week with the same pod? Last time it worked fine the second week. I just changed to a new pod, and it seems everything is working fine.

I spoke too soon. The new pod took one hour to go to 39 and is stuck there.

And I was so careful with the location and insertion. It seemed to go without a hitch.

Something must be wrong with the transmitter or the receiver.


I was told to do a Finger Stick BG (FSBG) before every insulin dose. I then enter those in my Dex. This keeps me very close so I can watch my curves.

Thanks Jay,

Finally my new insertion has settled down. But as you can see above, each time I did a BG, it was far away from the Dex.

All the red stars are BG entries.