Looking to Hear Some Personal Experiences of Those Who Have Used the Dexcom G5 & G6 CGM

Big YDMV here, but personally I like the G6 MUCH better

The G5 for me would lose signal all the time (even with my phone at hand), and that rarely happens with the G6.

The G6 is way way more accurate for me than the G5. I stopped using the G5 because I found it frustrating in that it was really unreliable for me. The G6 is not by any means perfect accuracy-wise like I was kind of hoping for/expecting, but I do trust it way more than the G5. The most the G6 will be off is by 50 for me towards the end of a sensor life. Based off a general feeling (no official testing), I think the G5 was more accurate than the G6 in only low ranges (below 60) for me.

I never had luck with extending sensors with the G5 (too many lost signal issues and inaccurate readings). I cannot extend ALL G6 sensors, but for the ones that have been accurate even at day 10 I will try extending. On average, IF I extend, then most of the time I get about ~13/14 days of sensor life total (the most I’ve gotten was 21 I think). I walked into using the G6 thinking I’d be able to extend all sensors and extend them for 20+ days. That hasn’t proved to be true for me, YDMV.

Insertion with the G6 is SO MUCH BETTER. Nearly painless and easy to do (unlike G5!!!) :slight_smile:

Adhesive on the G6 definitely needs help to make it 10 days alone and definitely more for if you’re extending. Investing in skin tac and sim patches was the move for me.

Overall, I went into it with the impression of “no more finger sticks yay!” based off ads and others stories. I still finger stick for treating lows and for corrections, but I trust the G6 trends it shows me and it has proved to be accurate (within 20) the majority of times. But definitely at times it can be off by 30+ (depending on how quick you’re rising, falling, or if it’s just not a great sensor)


Very well said, and I can personally attest to most of what you have said now that I have started using the G6!

I started with the G5 and couldn’t wait for the G6. The main issue for me was the no calibration required. I agree that the accuracy is much improved. The tape/adhesive SUCKS though. if they could just put the old tape on the new G6 that would be great!


You may have one of the early batches. They changed vendors and then went back to their old vendor (I think I am remembering this correctly).

Last two shipments, they have stuck just fine on my son with one Grif Grip over the top.

1 Like

Just in case you haven’t tried it, I clean the area and the same as the G5, I put a light coating of skintac directly onto the G6 adhesive, wait until it’s properly tacky then apply. That works through daily exercise, swimming etc and lasts for a few weeks :slight_smile:

I have been using dexcom g6 since may 29, 2019. It worked very nicely for me since, except one time I got a bad sensor and another time a bad transmitter. Dexcom graciously replaced both. Today, as I replaced a new sensor, warmed up after 2 hours, started reading, then came a sudden low of 65, then 56 right before my dinner time. Immediately i started my dinner and it started to go lower, mind you, definitely i did not take my insulin because I was on the low already. Because i didn’t feel hypo, i decided to calibrate. 1st time i got 234, entered it, got calibration error with the direction to calibrate in 10 minutes. 2nd cal. 222, same error, 15 minutes later, 3rd cal. 215, same again and again, any advice would be greatly appreciated.

1 Like

Mine has been out of wack a couple of times, but I can’t recall anything (at the moment) that was this bad. I suggest talking with their care team, they will talk you through pretty much anything. Besides that, maybe trying to find a well known diabetes educator would be helpful. Good luck!

Dexcom Customer Support Line: 1 (888) 738-3646

You’ve probably got this sorted out already, but, in my experience, when it gets in that pattern of repeatedly asking for calibrations, it’s never coming out. You’ve got to start again with a new sensor and a new warm-up.

I regularly have the problem of false lows in the first 24 hours. My advice in the future is not to attempt to calibrate when it’s reading super low. It will, more often than not, come back and become more accurate on its own. (And, by days 3-10, I usually find the G6 to be super accurate.)

The alarms are annoying, though, and just seeing those crashing numbers even when you know they are false is, well, alarming. Yours sounds like it was so far off that it may not have come back even if you had let it alone. Dexcom will, of course, send you a replacement. (Though there’s no replacement for all the time you lost with a new warm-up period!)

I don’t calibrate much in general, and, if I do, I would wait until it’s in a normal range and reading steady for a good 20 minutes or so.

We have almost never calibrated a G6, I would call Dexcom and get it replaced. As you mention they are pretty gracious, although it does take an hour or so lately to get through to someone and get the problem sorted. So we tend to do this on the weekends, which probably makes the wait longer…

We have been on a run of moderately poor luck, so we are calling Dexcom and getting additional sensor(s) about once every two weeks currently.

1 Like

Sometimes when I get blood in my sensor, the first day if readings are super low. I have called Dexcom and they will replace the sensor but the blood usually dries up in a day so it should eventually start working (but the alarms are super annoying).


Thank you for sharing your experience with me.

sheikh: Shaker Elsayed
imam @ DAH

I just started with the G6. Had been on the G5. I’ll not overly impressed. The no calibration is nice, sensors go on nice and stay well.
Getting sensor error warnings. Twice today and takes 2 hrs. before I get a read out.
I’ll call Dexcom in the morning and see what they have say.


Definitely not looking forwards to the forced switch that it about to happen.

1 Like

Yeah, G6 is funny. Some people have poor results and others have no issues. I’m one of those that have very good results with G6. The only issue I have is with the readings in the first 8 hours being off. But after that it is spot on.

Hopefully you just have a bad sensor. Good luck!!


1st of all - welcome!

I agree there.

Will you let us know what dexcom says about the sensor errors you’re getting? Hopefully they resolve.


Yup. Kind of weird. It’s a suppose to last 10 days. For me, so far, only 9 days. For you the first third of a day is non dependable. Still than a finger prick 10 or so times a day. Before I got the G5.

1 Like

Hi Honda. I compared them both side-by-side recently. Here is my experience with the comparison.

1 Like

I don’t use my phone only the Dexcom receiver. I had got a new one couple months back. So when I started the G6 it was updated. So I don’t know if it will still work with G5 sensors. Anybody know about this? Thanks Dwayne

My guess is won’t read G5, and slim chance to un-update. But Dexcom will stop supporting G4, G5 by year end anyway.

But you might be able to find someone with old G5 receiver, not in use, or online.
Or use xDrip.


I talked with tech support. They said it wouldn’t work oh well. So I found someone who could use the unused G5 sensors.

1 Like