Anyone else having weird fluctuations with their dex lately? Mine is way overreacting to minor fluctuations. For example dex showed me at 118 and dropping, did a finger stick 129. Dex then at the next 5 minute period showed up to 145, tested again 130. I called dexcom and they said the value is within the 20% it’s not a bad sensor but I’ve never had my numbers bounce like that during a period of steady sugars besides on the first day of the sensor which I tend to ignore. Just curious if anyone else has had this happen? I brought up transmitter too and they said it’s okay as long as I don’t get a transmitter error. Any tips on how to fix? I put a new sensor in and there’s a bit of bouncing but with the 1st day that seems fair and normal.
Does your regular meter need to be calibrated periodically? That may not even be necessary anymore but it used to be a thing (I have a couple of the same meter and now and then check them against each other so I don’t use the solution they used to have).
Also have you used anything containing acetaminophen? They say it doesn’t affect the G6 as it did earlier models, but tech support still asks me if I call with an issue.
My meter does not require calibration but good thought! I have a back up meter too and that one was in line with my every day meter. No Tylenol or anything with acetaminophen in it!
I’m going with: it is likely you will get a sensor error and early failure. If it happens, Call Dexcom, they will send a replacement one.
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Thanks! Called for the first one. My new sensor is off to a bit of a rocky start but only in the first few hours. Hoping it’s not a bum transmitter.
@Tee25 they are really bad the first 8-12 hours. I turn Bluetooth off and ignore my sensor for the first couple hours or overnight if I change one at dinner. Then I look and if my blood sugar has been rock solid and Dexcom is reading differently than my finger meter, then I’ll calibrate. It’s been working great other than those first hours. Give it time. Good luck 
Thanks! I definitely think it’s a dud batch. 36 hours in and it was showing me dropping from 155 while actual sugars were 207. Dex replaced so hopefully my replacement sensor works!
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I had something similar happen to me recently, but it was on the last day of my old transmitter and the first day of the new one. I wish you good luck with the new sensor!!
Thank you! I’ve gone through 3 sensors in the last week and now my current dex sensor (I just put on after 72 hours with the last one that wasn’t tracking rises or drop) and now I have a sensor error right before bed. Dex swears it’s the sensors and not transmitter, but I haven’t been through a bad luck streak like this in a long time. Normally I just roll with the 20% difference but my latest sensors have been showing me at 130 and I was actually at 175. So frustrating to not be able to trust the dex!
May daughter’s G6 sensors have recently been fairly erratic as well, so much so that I’ve had her doing a lot more fingersticks since I didn’t trust what the Dexcom was saying. Several times lately, the sensor was alerting her that she was (very suddenly) 50 with an arrow going straight down but the finger stick showed 114. That’s a huge discrepancy. Typically, when that happens, the sensor gives us three dashes at some point the same day. I’m grateful that Tandem always replaces the sensors when they “act up” but it’s frustrating nevertheless. Control IQ can’t do its job well when based on wildly incorrect BGs.
During the past 3 months, we’ve only had 2 sensors last the whole 10 days.
I had the same time about a month ago. I get a 90 day supply. So three sensors come on a box. I had all three sensors give very irregular readings. Dexcom replaced them all. Also all three that were replaced had the same lot number.
That’s nuts! Yeah I got frustrated with all of the last 4 for being extremely off. Dex replaced them all so happy about that. I used one of the replacement sensors and I’ve been within 10-15 points! So much better to actually trust what I’m seeing 
hope you guys have better luck soon!
Yeah that’s exactly what happened to me too!
@dsiizuka @Hertz4319 @Tee25 this might not apply but sensor errors are sometimes caused by compression lows. There are some conversations on the forum with errors explanations - you can search for the term. Don’t know if that helps but it might be worth checking.
For me it was not compression low. First they happen while I am awake during the day. Second when sleeping I don’t sleep on my stomach. Although I do have the sensor on my stomach.
Thanks Dorie! I don’t think it was due to sensor location on stomach. However, I was just woken up by a high alert of my dex. Checked via finger and was actually 30 points lower. Right now the sensor is on my upper thigh and I don’t think I’m putting pressure on it but here’s my graph from overnight. The low period I did not actually drop, but had calibrated not too long before my sensor at the time was showing 130 something and I was actually at 101. The graph went back to normal after the “low” without calibration. After that though I have no idea what was happening, I just know that I was also woken up at 12:30ish with a high alert, recalibrated because I was 20% lower and then an hour later I got my high alert again and was still 20 points lower. Does this look like a sensor that has pressure on it?
There are some other users on the forum whose analytical skills far outweigh mine. I don’t know if there’s a way to determine if a graph indicates a pressure issue but if so they would be the ones so I will defer to any who might want to take a stab. Attached is some documentation from Dexcom - add you probably know their sensors should be match within 20% of a fingerstick reading.
If your high reading was 400 (and of course I hope it was not) and your meter showed 320, while such a big difference is obviously cause for concern it would be within specs, so they recommend fingersticks during highs and lows to see just what we have to deal with. It can take some time to bring a high down and there may be some fluctuations which even non-diabetics probably get. When I’m coming down my graph may show little waves along the way, rather than a nice straight line.
One of our very analytical members posted the following about washing hands in a discussion on Dexcom accuracy. I thought I would share in case it affects your calibrations. I included the entire response but that part is mideay through the second paragraph.
Thanks for sending this!
New version of Dexcom G6 (1.9.0) several posts in various social media sites have this reported .
I am using an iPhone 12 Pro Max and have NOT seen this.
Thank you! So app glitch makes sense. My phone automatically updates. Hopefully they fix the bug soon! I have an iPhone 12.
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