@mohe0001 this one is for you, mostly, and me, a little.
In Dan’s article he looks at the kind of Dexcom CGM wipe outs I’ve observed and commented on for years. The article is certainly tl;dr, even I skimmed it. Yet he has set down a mighty piece of evidence, researched and backed up by his own original work.
I’m posting this topic because, while boring and technical, it really is important. I reached the same conclusions myself a couple of weeks ago; I made the same point (in a private communication via my health providers website) that spastic CGMs are dangerous.
I’ve had some similar concerns about the jumpy BG data from Dexcom G7.
I don’t consider the G7 data jumpiness to be dangerous though with the Omnipod 5. The Omnipod algorithm moves at a snails pace with the micro bolus, effectively smoothing the data by it’s slowness. Maybe the bolus calculator could become dangerous if it used a momentarily bogus BG number?
Here’s a sample of the jumpiness I’m referring to:
I’m curious if others think that this degree of jumpiness on Day 3 would be bad enough for a replacement from Dexcom product support. (I kept the sensor going and it settled down by Day 5).
Just a couple of days ago I was driving back from New Jersey to Boston and my Dexcom G6 went wonky, informing me that my blood glucose was so low it was unmeasurable. This inaccurate information set off alarms on watch, pump and cgm. This went on for 2 hours or so.
No big news. We’re all used to this. For me, it happens more than 50% of the time about 2 hours after a new sensor is inserted. The sensor is then fine for 10 days. But the first 4 hours are often very rough.
Has anyone seen any documentation from Dexcom on this? I haven’t.
Personally, I think documentation is important. It’s a minor irritation if you know about it, but could lead to bad treatment if users don’t know to ignore it.
I view the Dexcom G6 as reliable enough yet it still needs a sober adult in the room if it is positioned as the basis for realtime insulin delivery as with an AID system. My Loop DIY allows me to switch off the closed loop and I’m not shy about doing just that if the CGM is not earning my trust.
First day jitters are one thing but longer-term delusional dives and excessive elevated and inaccurate excursions test my patience. I’ll allow a few but I’m fairly quick to pull the plug on an ill-behaved sensor. I just physically remove the bad actor and let the software eventually report a “failed sensor” so I keep replacement police from reflexively denying my claim.
I’m seriously looking into the Eversense 365 as the solution when my G6 supply runs out later this year.
G6 would definitely be considered “delusional” (genius term) for the first 12-24 hours for me if I didn’t pre-soak. This is driving some concern for me with G7, but sounds like I can let it sit for 12 hours at least before truly starting it.
@Terry - how do you go about the process in your 2nd paragraph above? I’m reading that you get the sensor to error itself out?
Eversense 365 looks interesting, but the idea of having adhesive on my skin in one place for a solid year seems like a lot. My skin isn’t that sensitive, but I think it might not fare well being covered up for a year. Can’t wait to hear about others’ experience.
@JessicaD – If a sensor is beyond a reasonable chance of redeeming itself, I physically remove it and wait on the software to report an inevitable “sensor failure.” This is logged as a hard failure and there’s no dispute with customer service. (This tactic was suggested to me by another TuD member. It works and makes my life easier. I don’t abuse it.)
Then I go ahead and begin a new sensor session. I may have already inserted a new sensor. When my sensor lasts the entire 10 days, I presoak it 16-20 hours in advance.
I insert the next sensor 16-20 hours before it starts to report. This allows the sensor filament and its enzymatic coating time to settle into the new tissue. The old sensor completes its last 16-20 hours of service during this time.
I.e. before the transmitter is inserted (this is G6 only). I tried it once and when I inserted the transmitter (I only waited a few hours) the receiver pretty much immediately said that I couldn’t restart a used sensor. I didn’t try it again obviously; I’d lost a new sensor.
Since it does work for some people it is pretty clear either that I have really weird skin (maybe I’m not a human, or maybe I’m the only human…) or that there are significant differences between how Dexcom sensors react to different people. Both hypotheses are supported by the observation that some people could run a single G6 sensor for other a month (with restarts) but I could barely manage to get 10 days.
The G7 is the same for me; the 15-day G7 stops being functional after around 12 days because of repeated spasms; i.e. errors like those @John58 reported but morphing into the “temporary sensor failure, wait 30 minutes” variant. In both the G7-15 samples I tried (endo samples, so carefully curated by Dexcom) even the new aggressive attempts to ignore the ever more frequent errors officially failed at the end of day 14. (Dan Heller’s article struck a chord here as the G15 experience was very recent.)
Correct. Presoaking, for me, is the time when the sensor is in place without a transmitter. I always (G6 only) ensure at least 15-20 minutes elapses (especially two sequential sessions with the same sensor code) without a transmitter on any sensor.
Your G7-15 experience and my pessimism regarding a successful G7-10 experience will likely steer me toward the Eversense 365.
@Terry: I’ve been leaning toward the Eversense 365 but for a different reason. I’m making plans to try the Twiist pump (which presently only communicates with Libre and Eversense CGM). The pump is looking like a long term project for me because my Medicare Part D insurance requires a formulary exception to cover it. The Eversense 365 coverage sounds straightforward under Part B, according to the Eversense sales people I’ve spoken with. They seem to be proactive and knowledgeable about the steps needed to start Eversense (There is a contact form on the Eversense web site to start the process).
It all starts with a prescription from your doctor. The only glitch I’ve discovered so far is a lack of trained/certified MDs in the Seattle area to insert the sensor. I was told there is one in Portland and one other will be starting in June in Tri Cities WA. I will be trying to schedule that insertion after mid April.
Bringing my comment all the way back to the OP topic: My reason for trying Eversense 365 is not lack of reliability of Dexcom G7, but lack of compatibility of Dexcom with my next planned pump (Twiist). I hope to maintain a stockpile of a few G7 sensors just in case the Eversense is not a good fit for me.
I’ve been told that the Eversense is compatible with the AID system that I use, Loop DIY. It requires using an experimental branch of the algorithm but many have been successfully using it. I could then use my current pump, the MM 722.
I prefer the Medicare Part B DME coverage for both the CGM and pump and I’m disappointed that Sequel chose not to support Part B.
I’ll be interested in your experience with Eversense as you appear to be on a timeline ahead of me. I’ll be looking for a doctor in Portland to implant it – late this year or early next.
Yes, that’s what I thought, but then @andrea8 's experience with Medicare and getting twiist covered under Part B turned up… Here’s Andrea’s original post:
Then here is the clarification; I’d made all sorts of assumptions about the original post but the worst was that Andrea was on Part C… This corrected my misassumptions:
So Andrea is using twiist on Part B and has a Medigap (“supplemental”) which ends up covering it. Medigap if correctly chosen covers all Part B expenses after the deductible ($283 this year, 2026). Here’s my summary (after I’d worked out my mistakes):
This, finally, is all reasonable. twiist, despite the Tech Bro denial, is clearly a durable pump, so clearly a Part B item. This is ~great~super.
Not so fast, the people at Sequel told me the opposite. There was no ambiguity.
Before you get your hopes up it would be prudent to keep bugging the Sequel sales reps until you get their attention and have them check your coverage.
Sequel have limited control over our Federal government.
And Sequel do not have control over whether their precious pump is covered under Part B or not; that’s down to the CMS (as the contractors, the administrator, which controls Part B coverage).
So why believe Sequel when Part B covers twiist? Why not try; just do it.
I could be wrong but I was always under the impression that the Medicare Part B DME eligibility and the Part D pharmacy benefit were mutually exclusive. Here’s the result when I posted this question on an AI search:
is sequel’s twiist insulin pump eligible for medicare part b dme coverage?
AI Overview
No, Sequel’s Twiist insulin pump is not currently eligible for Medicare Part B Durable Medical Equipment (DME) coverage. Sequel has stated they are focusing on making the Twiist AID system available exclusively through the pharmacy channel (Medicare Part D), not the DME channel.
Coverage Channel: Twiist is classified as a pharmacy/Part D benefit rather than DME.
Medicare Part D: Because patch pumps like Twiist are often considered disposable or pharmacy-dispensed, coverage is typically handled through Part D plans rather than Part B.
Alternative Coverage: While not covered under Part B, you should check your Medicare Part D plan for coverage of pharmacy-dispensed pumps.
Savings Restrictions: The twiist Savings Program is not valid for individuals enrolled in Medicare or other federal/state program.
In the complex arena of Medicare rules, I know that it’s difficult (maybe impossible!) to discover an ultimate truth that will not vary. I’m interested in this issue because eligibility for Medicare Part B DME coverage is an affordability issue for me. Twiist checks all the boxes for me except for its apparent classification as a pharmacy benefit only (not even eligible for appeal). Like I said earlier, I could be wrong, in fact, I would like to be wrong in this case.
Medicare has two “coverage” codes for insulin pumps; “insulin pumps” (the original code) and “disposable insulin pumps”, the code created for the Omnipod. Insulet (Omnipod) initially tried for coverage under Part B but there were objections. This may be Omnipod was not offered under a “capped rental” scheme (“lease-to-own” or “hire purchase”).
It’s a cost issue for me too as I pay an extra $2,000 a year to use Omnipod just because it gets the disposable code.
Most of the Medicare code discussion has, unfortunately, been lost as it was on TuD. To complicate things the rules are set not by Medicare itself but by a part of the Federal Government, the Center for Medical Services (the “CMS”) which is effectively subcontracted by Medicare to administer the benefits. This is the same as Blue Cross being subcontracted to administer state or employer health benefit plans. The CMS rules start here:
Etc, etc, etc. Read section IV then look up all the E codes in there. Note that there are specific rules for AIDSes and the twiist combined with the CGM is an AIDS. A doc can separately prescribe Omnipod Dash pods with a CGM and this is what I have; so I’m not covered under the AIDS rules. It’s not clear if the O5 is covered without a CGM but I suspect that is up to the supplier (see below) because there doesn’t seem to be an “AIDS” E code.
All of the CMS rules are implemented in a way that makes them descriptive of the device. They don’t name specific devices. @andrea8 got coverage under Medicare with the balance paid by medigap. The information is somewhat scattered through the posts but @Terry you are on that thread too:
In this scenario the twiist and CGM (LIbre3+) come from a DMEPOS supplier (Byram, Edgeware, Edwards etc) presumably as an AIDS supply. The supplier gets the diagnostic information and maybe the codes from the endo (an endo is pretty much a requirement), makes sure all the requirements are met, and bills Medicare via the CMS (the administrator).
The medigap coverage is not involved in this; Medigap is pure insurance and is secondary insurance. It picks up the bill after Medicare has finished paying. The coverage is determined solely by the plan letter; the plan provider only affects the premium. Medigap is also for life; it can’t be cancelled by the insurer so long as the premiums are paid etc.
What does matter, however, is how it gets billed to Medicare and this is, at best, arbitrary. Here’s a PDF on the CMS web site:
Horrible, unnecessary, stupid. I believe the 2028 changes to this are still on-the-books and that will change everything to a pure rental model; not lease-to-own.
@jbowler and @Terry
If you read up on the details of the Empire plan in NY State for retirees/Medicare enrollees, the plan is a specialized Part D plan specifically for retired NY govt. workers. I think some of the terminology used in her previous descriptions of the coverage described it differently and may have caused confusion.
I too would like the twiist to be covered as DME under Part B…But I don’t think it is going to be feasible in the near future. I am now directing my efforts to the formulary exception process required to get it covered on my Part D insurance, and to starting Eversense CGM. Hopefully will have success this summer.
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