@Sjwprod I am not sure which of the FDA’s letters you read, but you need to read this thread, where @bkh analyses the FDA letter. Documentation was the least of Dexcom’s faults!
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Sorry I made a typo “20” should be 10 in the above.
Latest news today from Dexcom Investor Relations, G7 15 day launches in the US on 1 Dec 2025.
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@elver Thanks for posting this. I hadn’t seen it or checked Dexcom’s announcements recently. I have an appt with my Endo next week and planned on asking him if he’d heard anything and when/if he’d recommend a switch (I expect he’ll say, let’s wait an see how it’s received); gives us more to discuss as they’ve finally announced it! Probably more to the point is whether the DOD pharmacy I use will support it; not to mention whether it will work as advertised for me for 15+ days. I’m a bit concerned about being limited to two per month, the sensor not lasting, and Dexcom’s regular use of ground shipping that seems to take much longer (10 days avg) to arrive. I’ve said elsewhere, I think it’s the same sensor, just re-packaged in a wrapping extoling their claimed 15-day life. It will also be interesting to see Dexcom’s price point, i.e. whether they plan to charge more for the perceived same product due to the 5 additional days (at least for the roughly 3/4 of folks it supposedly will work for). Adds a wrinkle to many people’s decision whether to switch or not! My distrust of corporate America may be showing a bit here… Anyway, thanks @elver!
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Thanks for the update! That’s exciting news, I’m looking forward to the G7 15-day launch in the US on December 1, 2025.
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One less thing to think about. Fortunately for me the g7 adhesive is like super glue, so don’t imagine I’ll have issues keeping it on for 15 days.
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See attached S/E Decision Summary for the 15 day sensor. It appears a design change was made to the algorithm but it’s not explained in detail in this summary. Summaries are posted about 30 days after clearance. The details of the change would be in the actual submission, which is not made public unless you submit an FOIA request.
https://www.accessdata.fda.gov/cdrh_docs/reviews/K243214.pdf
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Not true. The 10.5 days start when you activate the sensor.
I find that when you put on the new sensor in advance it usually activates pretty quickly.
The report says there is a different algorithm and, if I read correctly, the warm up time of the 15 Day version is an hour/60 min while the regular G7 is reported as 27 minutes. There’s no indication a physical difference exists.
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Not sure if you mean physically different from a design perspective but the change in length of use and the software change was enough to make it a significant change, thus requiring a traditional submission to FDA to get the changes approved.
However there will have to be some physical differences in the way the 15 day sensor is packaged/coded/labeled in order for the two devices to be distinguished from one another - both from a mfr and a patient perspective. That would be addressed in their risk assessment documents (in the submission) as means of mitigating the risk associated with someone thinking a 10 day sensor is actually a 15 day sensor. Samples of the new labeling would also be included in the submission.
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This explains why EHCS has been repeatedly trying to get me to apply for another 90 day supply of the old G7 for the last month or so.
I’m not going to do that. Despite my cynical comments (well, in fact, because of them) I’m going to go for a “15 day” ASAP; my problems are the first 24 hours, not just the “pull loop” but also the completely flakey readings.
Of course my other choice is to swap to Libre 3 now 
They’re going to charge 50% more; you get 15 days for 2 sensors rather than 30 days for three of the old ones. They pay exactly the same; so you get the same thing for the same price and they make the same thing for 2/3 of the price. Money, money, money.
Of they could behave like capitalists and sell two for less because two costs them less to make. Alas capitalism is dead, if, indeed, it was not stillborn.
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So you will have to wait until 1 Dec and go thru DME if you want to be one of the first to o get a 25 day sensor. Pharmacy channels are expected to be the 2nd phase of the roll out.
It will be interesting to see if the 1 hour warm up and new algorithm is worth the hype.
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I normally try to overlap the old G7 by the max, i.e. 8 hours, and even then it is still flakey. So long as they still support the overlap (i.e. by having a lifetime of at least 15.5 days) I think that is a certain improvement. They are acknowledging their own BS and rolling back the “30 minute” warm up time.
I have no problem running two G7 sensors in parallel for 24 hours. Quite a lot of the time I don’t get round to taking the dead one off anyway. I’ve got two arms, what’s the problem? This all sounds like an improvement. An improvement in their marketing, not their tech.
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@jbowler The variation in how people do the swap our of sensors is amazing. Apparently you max out the cross over time; I, on the other hand, try to minimize it, allowing a “just in time” end-of-grace-period approach so one sensor dies just as another becomes somewhat useful . My approach allows a slow build-up stockpile of sensors. I imagine most do one or the other depending on their insurance coverage; though for me that’s not the case (Medicare and Tricare for Life is currently a good insurance combo as I pay virtually nothing for the great majority (it may change as DOD keeps changing retiree coverage, despite having told folks medical coverage would be free for life when I began service!). I’m sure it varies widely amongst all of us!
That said, while I like the 30 min warm up time before readings are available, my experience has shown a wide variance in accuracy for the first hour up to the first several hours…right on target upto 50-60 mg/dl points off (i.e. some sensors are frustrating slow to actually “warm up”). I chalk it up to needed improvement in Dexcom’s wire coatings and my personal blood chemistry that erodes it.
I’m right there with you on the adhesive, though; no need for an over-patch (again, I presume individual body chemistry); that little ring of G7 paper/cloth is sometimes difficult to get hold of and peel off, resulting a bit of tug-o-war and more scraping it off than peeling! I know there are others for who it doesn’t stick well at all! For me, I hope Dexcom hasn’t changed the adhesive with the 15 Day version; for others, if Dexcom has, I hope it works better for all of us!
Do you know the Dexcom price points to be offered or are you presuming based on history? I think you’re probably correct, but Leach seems a bit more trustworthy than Sayer (probably optimism on my part).
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@funk I was refering to the sensor itself, vice the packaging which would have to change to avoid confusion. The document provided above clearly states the algorithm changed, its much less clear on sensor itself changes, though I understand the wire make-up and coatings may change based on the FDA warning letter to Dexcom and their COO (soon to be CEO) comments on-line (I think its in this one: https://www.youtube.com/watch?v=N8lJzuFgdY0.
I used the Libre 3 and Libre 3 Plus prior to the Dexcom G7. The Libre 3 Plus is a fifteen day sensor. My experience on the Libre 3 and Libre 3 Plus, was a 100% failure rate. If it wasn’t the sensors failing part-way through the fifteen day period, it was fifteen days of grossly false readings, and regular low-glucose alarms, resulting in constant fatigue from so little sleep. It just never quit. I moved to the Dexcom after I ran out of patience with the Abbott products.
Thus far, the G7 has proven a 90% failure rate. When I say failure, I don’t require the sensor to quit, or quit transmitting…but that’s happened enough that I typically apply three sensors to get one good one, and that may or may not last long. I got a sensor working this last time, and it failed after three days. I’m to a point where at any given time, I have one or more replacement sensors coming from Dexcom, to replace failures. The last one simply fell off after three days.
I’ve also come to a point at which I can’t put the sensor on without unbearable burning, swelling, welts, weeping sores, itching, irritation, discoloration, swelling, and something with the appearance of chemical burns. The overpatch does worse than the actual sensor, but anywhere I put the sensor, the skin is disturbed that way for another thirty days or more. I have a spot that feels like leather, like a partial-thickness burn from a previous sensor placement. It was actually a relief when the last one fell off, having lost its adhesion.
The one advantage that the Dexcom seems to have over the Libre sensors is the ability to “calibrate.” With the Libre sensors, I could record the finger-stick glucometer readings, but the recording of the glucometer readings didn’t influence what was displayed by the Libre 3. At least with the Dexcom, inputting a glucometer result has some influence on what the Dexcom sensor shows as a blood glucose value. The first twenty four hours seem to be a learning event for the sensor; by the time the end rolls around, however long it is, the sensor seems to be close.
Much as I’d like to see a fifteen day G7, they’d need to show enough reliability to make it the fifteen days, or the ability to leave it in one place without the burns or reaction or whatever is going on, with the adhesive. Presently I started one with a film-wipe, which is producing considerably less irritation, though it’s still there. I’m familiar with the extremes to which some go to make these things work (flonase, trimming underlayment, yada, yada…) it shouldn’t be necessary to make a product work…especially not one that’s supposed to be the gold standard of CGM’s.
Had my Endo appt today and asked about his understanding of the G7 15 Day version. As expected, his comment was to wait and see how it’s working with others until our next appt (May). I’m pretty much in agreement…don’t by .0 of anything, particularly 1.0! Of course I’m using 0.6.0.16 of Trio, so….
Any way, he was thrilled with my TIR, wasn’t concerned with post meal spikes that don’t go too far or last significantly long, said not to worry about them. Surprisingly, I’m the only patient he has on a DIY system and Dash; said he’d ask the Omnipod rep how long they’ll make it and let me know. Said most of his folks using Omnipod have moved to the O5, but with TIRs about 15-20 pts lower, bg’s 15-40 pts higher, and less controlled overall. He commented he hopes an implantable solution for T1 and 2 comes up before he stops practicing! Me too!
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@Carbless, this thread on handling adhesive allergies may help with your problem. You need to use a barrier bandage under the sensor whose adhsive you are allergic to. It’s a common problem.
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I received this email from Tandem today regarding use of 15 day G7 sensor with Tandem products:
Please note that the Dexcom G7 15 Day CGM System is not yet compatible with Tandem Diabetes Care automated insulin delivery systems.
Do not attempt to pair one with your Tandem pump.
You may continue to use your Tandem pump with either the Dexcom G7 or Dexcom G6.
Tandem and Dexcom are working closely together so we can bring you this integration, and we anticipate compatibility by early 2026.
We will notify you when you may start using the Dexcom G7 15 Day System with your Tandem pump.
Thank you for your patience.
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