Back again to talk about the G6 and 5 failures in two days

My experience with the G6 has gone from horrible to horrendous. I went on vacation yesterday and brought seven sensors with me yesterday I had three fail. One didn’t separate from the inserter. Two more had wildly off numbers. CGM was reading 285 and my BG was 140. I calibrated multiple times in 12 hours and it was off by 40-100+ points. I changed it The second one at 3am alerted me to a severe low of 40 with two arrows pointing down. A finger stick showed a BG of 128. I removed it and switched to a Libre for the day. Now I just tried a new G6 and less than a minute after inserting it it began alarming LOW. Skipped warm up and I wasn’t low. When I called dexcom they have now informed me that in order to receive replacements a supervisor must approve them. This is a new policy that started a few months ago according to support. That’s exactly when all of my issues started.
So needless to say my vacation is ruined and I am probably going to head home tomorrow. The stress of this is off the charts.
I am just venting but also feel so despondent. I work so hard to remain healthy. Diabetes, as we all know, doesn’t give us a break, ever. The management is relentless. To have medical devices that are making it worse and elevating my stress which really impacts my control, I just don’t know what to do.

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Ugh. I am SO SORRY you’re going through all this! And a ruined vacation :weary: But I understand. I depend so much on my CGM and pump and panic if anything is off.
So far I’ve had great luck with my Dexcom G6. If it’s off - usually one or two calibrations resolve it. I do on rare occasion have a number that seems off but mainly very accurate. I haven’t tried swimming or major activities so don’t know if those are things you might be doing that I don’t. I’ve heard some people end up going back to injections and finger sticks because they haven’t had good experiences with the equipment
I don’t have any advice but I hear your frustration. I Hope something happens that will improve your luck. Thinking of you

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@Spooky some people find one CGM better than another. Some people find that CGM just doesn’t work for them. It is a tool, and CGM has advantages and disadvantages even when they work correctly. But if it doesn’t fit your needs, imo, maybe you’re better off with a good finger stick meter? There’s no magic here, if it’s not working it’s not working. Good luck in whatever you decide.


A basic question @Spooky, why do you even bother trying to use a G6? From what you have reported [posted], it is quite obvious that your body and G6 don’t get along. Why cause yourself so much frustration. Dexcom works very well for many/most users but, like any device or medicine it can’t be expected to work for everyone.

And why would something like this ruin a vacation? I took many, many vacation trips for 60 years, while dependent on insulin to live, BEFORE I began using a Dexcom and fully enjoyed my time - add to those vacations countless number of flights for business.


Have you tried the G7?

I’m so sorry this happened to you.
Dexcom is known for giving false lows the first 24 hours. I didn’t used to have that problem but have noticed it recently with multiple sensors.
I’ve occasionally called for a sensor replacement and wasn’t told about supervisory approval - they simply said they would send a replacement. You’re not doing anything wrong, but it may be that some users have such frequent issues, Dexcom needs to get an additional level before sending one out as a matter of business practice; and I would hope it would be a quick process given the reason for the device.
Do you use Tandem with CIQ? If the Dexcom isn’t working you could turn off CIQ and run your pump in manual mode, using a Libre for your readings instead if that one is more accurate for you. You may need to check (swipe) me frequently to see if you need to make any manual corrections but it is do-able. If you’re using a handheld receiver I wonder if it could be defective?
Again, so sorry.

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Have you tried a new transmitter?
I once had a bad transmitter that caused lots of inaccurate readings. A new transmitter fixed all the issues.

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Dennis - this was a good reminder for me. Since I’m 67 and new to T1d and always depend on these devices I sometimes panic when there’s a malfunction. I always carry pens and finger stick items when I travel especially. When you’re used to depending on technology it’s easy to forget those weren’t here forever!!


I have used the dexcom for 4 years with no issues at all. Maybe Called in one defective sensor in all that time. I am dependent on the system now. I had a health scare two years ago that was eye related and traumatic and now have panic issues surrounding management. It’s ruined my vacation because I spent the first 36 hours of it trying to fix the system and then get my numbers back where they need to be. Stress is tremendously bad on my control. I went old school for the last 24 hours with finger sticks only and it just doesn’t cut it. I also tried a Libre and the readings are really off. Close to 45 points at times. I spoke to my doctor who said that it’s not accurate that a cgm doesn’t work with some bodies. I believe that there is a quality issue with dexcom that has happened this past year.

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I am not very active. Just taking walks etc. no beach or swimming. I’ve lost a lot of weight over the last two years but still have plenty of padding for the sensor. I really do rely so heavily on the cgm. It’s funny because I was resistant to using one at first. I even returned one years ago. But now it’s essential for me.

I haven’t done that but it really makes sense. Dexcom swears the transmitter has zero to do with the issues I am having. But I wonder. It makes sense to eliminate variables and this is one I haven’t eliminated yet. Good idea!

That’s exactly what I did. I shut off control IQ and manually bolused. I use the pump in a kind of off label way like that anyway. I do use control IQ but I do a lot of manual bolusing as the pump often adjusts with too much insulin for me. I have found the Libre to be not very accurate. It’s sometimes exact to a finger stick. Other times 20, 40 or even 60 off. Last night it alarmed with a 60 BG and when I tested I was actually 118. Then it stopped reading all together. 30 minutes later it was back and and about 25 off now for a few hours.

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I’m waiting for the g7 to work with my pump. I do have one though. I wasn’t sure if I start using that if I can go back to the g6 with the apps etc if needed. Seems like it wouldn’t make a difference. Are you using the G7? How is it?

Keep in mind that is not the number of points difference between CGM and fingerstick that makes the difference, but percentage. Dexcom - and I believe Freestyle - are considered accurate even if the numbers are off by 20%. Here’s an excerpt from Dexcom’s website (link is below if the chart didn’t come through). If course some of your numbers were far out of that acceptable range, and I’m not saying you do not have cause to be frustrated. Just a reminder that not all “off” numbers are errors, I’d it helps at all with your anxiety.
Compare the meter and your Dexcom G6 to see how closely the numbers match each other: if your G6 reading and meter value are within what we call the 20 rule (also known as the %20/20 rule), they match closely.

The rule

To use the 20 rule follow these steps using the table below:

  1. Look up your meter value in the greenmiddle column.

  2. The left G6 – column shows the low range for a G6 reading that’s a close match.

  3. The right G6 + column shows the high range for a G6 reading that’s a close match.

For example the orange highlighted row shows that if your meter value is 100 mg/dL, your G6 reading is a close match if it’s between 80 and 120 mg/dL.

@Spooky, Tandem has not yet been authorized (I haven’t checked today) to release the t-Slim software to permit the G7 to connect with CIQ.
When the software is released you may install that through The Portal and instructions will be in the training session on how to switch back and forth between G7 to G6 and G6 to G7; it is a “simple toggle” that will appear in the t-Slim “Options”.


Spooky, are you using the same sensor site that you did for 4 years previous?

I am terribly sorry to hear that you are struggling with your dexcom G6. I would definitely recommend reaching out to your endocrinologist’s office and informing them of the issues that you are facing. However considering that your pump only supports G6, there are few ideal solutions without changing the pump you use. Luckily it seems tandem will add support for the G7 in a few months, so it might be best to wait it out (and maybe use a libre as a backup), especially since insurance makes it very difficult to switch pump types.

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Hopefully your pump will support G7 soon. I’ve only been on the libre3 for 14 days and G7 for the past couple months. Found the G7 to be far more accurate for me. Never tried the G6 as I’m only a few months into being T1D and G7’s became available the day I went to pickup the prescription.

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I rotate around my stomach and have always used that area. I did lose a good amount of weight but that happened in the last year and the g6 was working perfectly for 8 months while at this weight

I thought I could bypass the pump like I have done for a few days with the Libre and enter manually but use the g7 as the cgm.