G6 Review (using sensor code + NO calibrating)

So, I decided to go ahead and give the 3rd option a try just to see how it went and I’m kind of blown away. Liam is on day 8 of this session where we entered the sensor code and we haven’t calibrated except maybe 2 times in the 8 days when the readings were just far apart from each other (talking > 50% difference).

Using this method has achieved us a FIRST this week which you’ll see in the below image:

Never before have we had a week where our 1 week “Severe Low” percentage was 0%. And this is WITH code and WITHOUT calibrating…as I said, I’m kind of blown away / shocked.

What I’ve found is that although his CGM does sometimes push him lower than he actually is the system is VERY FAST in our case at turning that curve and jumping right back up. We haven’t had any cases where he went low and stayed there.

I’m super impressed with this option and it requires less effort (no calibrations required) so I may stick with this method moving foward if the CGM continues being as responsive and accurate as it has been during this week.


You have seen the light, enjoy the peace and quiet and extra time of no calibrations. I hope it holds for you, this is exactly what we have been doing. It is so lovely to just not have to fiddle with the damn things.


I agree, this is mostly what I experience. There are outlier sensors, but mostly I try not to calibrate, and wait for the sensor to get back to the expected range.

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I rarely calibrate G6, and only do bg test when I have symptoms or instinct tells me dexcom.might be off.


This is where we all end up once they see the light

I’m not saying I won’t go to using no sensor code + calibration. This will all depend on how reliable the G6 continues being in recovering quickly from it’s low dips. The method I’ll end up using long term will take more time to test this particular approach to see how reliable it is over a longer span of time. I loved the no sensor code + calibration method also; albeit, it was a bit more work.

This 1, 10 day period may be an anomoly - time will tell. Neither the G5 or the G6 have historically been accurate for us with highs over 250 and lows less than 60 and the systems have always taken forever to recover and move up by themselves…but this one week I’m excited by what I’ve seen and I hope it holds up.


Totally understand what you are saying, and of course understand that you are going to test out every option and go with the one that gives you the best results. I just have a hunch that for once, the easiest approach may end up being the best approach.


Another satisfied code-user here. I have stopped calibrating all together, even during the first 24 hours. No problems with accuracy. Still rarely getting a full 10 days though, probably averaging 9 days per sensor.


Calibrating in the first 24 hours is the worst idea altogether. That’s when the sensor is off because it’s freshly inserted not because it’s actually miscalibrated—- so if you’re calibrating it then all you’re doing is ensuring it’s not going to work right once it settles in

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We also successfully started our second session last night on the sensor we were already using. Using this method we had ZERO sensor error / disconnect periods during the first 10 days…so I’m now getting as much extra life out of the 2nd session as we can to help with that stash we’re still trying to work on.


This is the most frustrating time when your pump is relying on CGM data to make adjustments. There is absolutely no quality control with Dexcom anymore. You can have one sensor that’s absolutely brilliant that will be accurate for three straight 10 day sessions, and then the next one you insert will insist your BG is 350+ for 2 straight days. I don’t even know why they have a calibration option on the G6 anymore. I went into an endless calibration loop last week trying to calibrate a sensor that was reading 20 points higher than my actual BG.

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I had this issue during our session where I was testing Sensor Code + Calibrating as necessary…calibration loops were no joke. I would never calibrate; however, unless it was outside of the 20% one way or the other. But yeah, totally agree…the devices are sometimes a crap shoot…entire lots can also be brilliant, or duds.

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Unfortunately, you’re guaranteed to get into one of those endless calibration errors if the sensor is outside the 20%. I enter the calibration twice in a row to get the system to display exactly what I entered. This worked fine with the G5, but the G6 hates this method. I’ve never understood why the system doesn’t display the exact number you enter when doing a calibration. It literally divides the calibration amount by half, so what’s the point? I don’t think Dexcom even understands what the definition of calibration is anymore as evidenced by what’s happened to the G6 over the last few years.

Only if you are using the sensor code method. My second test was no sensor code + calibrating whenever i needed too and it worked wonderfully pretty much just as it had with the G5. Very few calibration loops and shorter when they did occur (one or twice -vs- five+ each loop)


I agree with the statements about the G6 sensor and the code. I have discovered that the problem is not with the sensor when it isn’t accurate with the code. The problem is with the sensor insertion. The insertion and insertion location are the variables that cause the accuracy difference.

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I’ll say it differently. The G6 sensor turns out to be somewhat picky about the body type and sensor wire placement. I’m hoping that the G7 works well in a wider variety of sites, because I’m one of the lucky ones where the G6 just works well with no fuss, and I want everyone else to get that kind of experience.

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I use the same area on my body for my sensors. I’ll die on my sword saying that insertion and location have nothing to do with the problems of the G6. It’s the ■■■■ poor quality control that Dexcom keeps lowering the bar on that is the root cause of these issues. I went on the G6 the day it was released and I never had the issues I’m having now. They keep d!cking around with the transmitters and the adhesive, the quality control of the sensors have never been worse.

I believe the reason the calibration does not reflect the actual glucose you enter for calibration is to take into consideration the “lag” time between interstitial fluid and your capillary glucose. If you stop trying to fool it, it will work better. For example, this morning my sensor said I was 110 but I felt a little shaky. I did a finger stick and my glucose was 62. I entered that and the new sensor reading was about 75. Well, 10 minutes later it was alarming that my glucose was 68 and I was headed for a low glucose event. I think we are trying to micro-manage things!
The system is not perfect but damn close.

When I was using the Medtronic system, they said to NOT try and calibrate if the numbers were wildly off. They recommended waiting until the numbers were closer (that system required calibration every 12 hours). They said to think of it more as a confirmation and it did seem to make a huge difference in accuracy!
I tend to treat the G6 the same way and my correlation has drastically improved.
If I see the readings diverging from my finger-sticks I try and wait a while and almost always things self correct. My endocrinologist, who is sharp as a tack, said try and let the system work as much as possible. The system goes astray when we try and force things. After a year on the G6/Tandem system I am inclined to agree.

BTW, to the person who is restarting sensors (which I do always), be prepared for sudden failures. Mine typically restart OK, but in the night, always in the middle of the night, I get sudden plunging low alarms. Usually on the third or fourth night. The used to reliably last 8 to 10 additional days but no longer. Sometimes I get 2 days and very occasionally, up to 10. Just be forewarned!

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