Dexcom: 138 Fingerstick: 305

And this is with clean, dry hands.
At this point the Dex is just a random number generator. We’re going to swap out tonight while he sleeps. What’s the most Dex has been off for you?

I’ve frequently seen it off by more than 100 pts when bg is moving quickly… did you see the post on here about “what is normal blood sugar” ?

Yeah it was not a moving quickly situation though…he’d technically been plateaud at 130ish for more than an hour. And it’s been way off for a few days (not quite that much, but at least 60+ points every single time we calibrate, which is on a flat line). We kept hoping it would recover but I think we just permanently screwed up the sensor when we put it on without the transmitter.

Did you test twice? That’s always a good idea when it’s that far off.

Yep: 298 and 305. So pretty close. This sensor has gotta go!

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Wow. Shocker. I am amazed by some of the violent swings you and Harold get. I know this one is clearly an unusual cause from what you explained.

FYI, my kid is about 120 lbs (I suspect weight has to do with speed of variability), and 95% of the time we have between 0 and 20 units of error. When moving very fast up or down I have seen 50. Once, after several compression lows (they change the calibration some every time) we were off 40. But that is once in 6 months.

How “Jumpy” are your dexcom readings? If I get prolonged “shaky” readings, I will go ahead and change it out.

Hey @TiaG - I know not ideal, but with those types of readings I’d just swap out for a new sensor. Every once in a while I’ll get readings like that and I’ll do one of two things:

  1. Stop and restart sensor
  2. If number one doesn’t work (you will know relatively quickly) then trash that sensor and put a new one on.

This is the type of behavior I would expect of a depleted sensor. Most of the time I change at the first sign of “noisiness”, but there have been instances of 200+ point differences between finger stick and Dexcom.

I would never even attempt to go beyond about two weeks at this point. It’s not worth it.

We had one sensor that was out of the box off like that, Dexcom replaced it.

100+ points quite a few times.

Update: We changed the sensor last night while Samson slept (a pretty good technique, if I do say so myself: he doesn’t wake up and he’s usually pretty flat at that time, so we don’t worry about surprise lows or highs in the warmup period.

Anyways, sensor said 89 this morning, finger prick showed 83. So for now at least we’re back on track.


yeah this is just what we get for letting him jump in the bath with the bare sensor. I totally blame us, it’s not even the sensor’s fault this time. But this is definitely the single worst sensor we’ve had…not just that one egregiously bad reading; it was basically completely off every single time we tried to calibrate.


We do this every chance we get! We usually take off the old before he goes to sleep then install the new one when he sleeps. It works like a charm most of the time.

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I am envious of that. This is something that does not work with a teen :slight_smile:

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I am really hoping Samson doesn’t have to deal with this laborious sensor change process as a teen. Worst case, the transmitter/sensor combo is tiny and easy to attach. Best case, he has a brand new cyborg pancreas thing going on.


Not sure if they can make it any less laborious, but with my teenager it takes less than a minute and usually doesn’t involve any squawking. Once in a while he gives a grimace.

Cyborg pancreas would be awesome though.

Ditto @TiaG

we spend an hour with his arm wrapped in saran wrap with lidocaine cream slathered on, then we wipe it off, then we freeze it for five minutes, and only then do we do the sensor change. So that adds some time. Then we dab the edges with skin tac, put the sticker over it, dab that with skin tac. Then we put unisolve on the defunct site, eventually peel it off, wipe down with alcohol, then spray with flonase and put aquaphor on it to prevent irritation. So it’s a pretty involved process.


Yeah, it will get easier as he gets older. We don’t use skin-tac, so it literally takes more time to correctly place the grif grip than it does to insert the sensor. My son does seem to have a high pain tolerance though, as one of his dia-friends goes through a process similar to yours even at 13.