Hi Joe,
I let a Dexcom G7 warm up on my left arm for 11.5-12 hours overnight. I calibrated my BG in the morning, and removed the old G7. I paired the new G7 with my pump. It didn’t give me any LOW readings. THANKS, Joe!
It wasn’t that far off from my BG meter. I was prompted for a calibration in the morning. I was able to sleep peacefully the first night and to exercise in the morning after the sensor completed the thirty minute warm up period.
My CDCES said that a Tandem rep can take your pump and change the software to let you go back to the G6 if you want to. I’m not sure how long the G6 will be around. She also suggested trying the Libre 2 Plus. Does the Libre 2 Plus have the same accuracy as the Dexcom has after the warmup period? The Libre 2 Plus lasts 15 days. Has anyone tried this sensor? Please share your experiences and thoughts about the topic.
Thanks SO MUCH!
Jane, there isn’t any reason for you to pass off your t-Slim to have it set back to the G6. Remember the “course” you took, and passed the quiz allowing you to upgrade your pump to either/both CIQ version 7.7 (G6, G7) and 7.8 (G6, G7, Libre)? It is a menu toggle under Options. It is HIGHLY recommended by Dexcom to avoid any attempt to calibrate either sensor within 24 hours following warm-up; and what you learned when you calibrated is that your BGM is almost as accurate as your more accurate sensor.
Given that the Libre2 Plus, one of only three home glucose devices Approved by FDA for calculating insulin bolus, you can assume that it is MARD rated within 2 of the Dexcom.
Hi, I wanted to add that I spoke with a Byram Healthcare representative, a Tandem representative, and our son’s endocrinologist, all of whom said Dexcom has plans to discontinue the G6; possibly by the end of 2024. Obviously, this has not happened yet, or even been announced by Dexcom but I think it’s a likely possibility.
Thanks, Dennis!
I’m staying with the Tandem/Dexcom G7 for now. The Dexcom phone representative was very clear in telling me to calibrate the G7 three times during the warm up period when I had trouble with it reading LOW. The ~12 hour warm up period in my arm was a great help. Thanks for the tip on the competitive sensor market and the accuracy they’re trying to achieve.
I’m a Kaiser Permanente member in California. I get my CGM sensors from Byram.
I upgraded my Tandem pump software so as to be able to use G7s when the new software became available, but had to continue using G6s because my resupply order was on its way to me when the new software became available. Now, I was finally ready to order G7s.
BUT . . ., Byram says they can’t switch me to G7s without a new prescription, and Kaiser says that my prescription is good through March 2025, and they won’t issue a new prescription until the current one expires. SO, no G7s for me for another 14 months.
Are other insurers taking the same position?
It’s not worth my making a big fuss with Kaiser since the G6s are working well for me and the G7s will likely only be a small improvement–not like the huge improvement going from the Medtronic Guardian 3 sensors to the G6.
John @schnauzer1, I never knew that an insurance company could write a prescription for controlled medical supplies. I suggest that you speak with your prescribing physicians and request that she/he write you a script for G7.
It is unusual that Byram didn’t just send the Px form to the physician of record for you.
Kaiser is a Health Maintenance Organization (offering Medicare Advantage Plans), not an insurance company. My prescriptions are written by physicians contracted by Kaiser.
I spoke to both my endocrinologist and the DME endocrinology nurse for the Kaiser facility I use. They both said I have to wait until my prescription expires.
Byram has a contract with Kaiser to furnish durable medical supplies. I’m guessing that Byram worked out with Kaiser that Kaiser would just switch patients to G7 as each patient’s G6 prescription expired.
Kaiser has been more than cooperative in taking care of my medical needs and providing top of the line equipment. I’m not going to fight with them over a relatively unimportant issue–especially since I don’t even know that I’d like the G7s better than the G6s.
One downside of the G7s: The user has to pair every sensor with the pump. With the G6, the transmitter is paired, meaning the pairing process is once every 3 months, rather than every 10 days.
Hi Dennis,
What type of BG meter/strips do you recommend using for calibrations?
Jane
Hi Spooky,
I had a G7 sensor fail after only two days.
Please share what makes a good upper arm placement.
Thanks,
Jane
Jane, I avoid recommending products on this site and restrict my suggestions/endorsements to devices and medications that I have used and report my experience. As my BGN is many years old, I’m looking for recommendations for a replacement; and that said:
As far as I know, there isn’t any BGM [home use blood glucose meter] that provides a glucose reading as accurately as the three FDA ApprovedCGM systems, the only devices approved for insulin dosing - in order of approval, Dexcom G6, Dexcom G7, Abbott Libre.
When looking for a BGM, consult results of testing services looking at MARD testing by laboratory testing of blood drawn from a vein. What you can do to validate the accuracy of your BGM, is when you have lab tests dine that include total plasma blood glucose is to do two [at least] finger-sticks at that time, one from each hand, record the results and then compare them with the lab report you receive the next day. Keep any differences in mind when comparing your BG readings with your SG display.
Something I noticed when reading the literature that arrived Friday with my new G7 [I’ll change to G7 when my last g6 finishes] is that Dexcom recommends at least two finger-sticks before calibrating the sensor.
Hi Dennis,
Thanks for all of your tips. It makes me very happy that the forum is here, and that you’re willing to share your knowledge and experience with other people with diabetes! Good luck with your transition to the G7.
Take care,
Jane
Lets be careful @Dennis One of the current standards for Self-Monitoring Blood Glucose Test Systems (SMBG) is
… 95% of all SMBG results in this study are within +/- 15% of the comparator results across the entire claimed measuring range of the device and that 99% of all SMBG results are within +/- 20% …
The current standards for CGMs that can be used for automated dosing are more nuanced. One standard is
… For all iCGM measurements from 70 mg/dL to 180 mg/dL, the percentage of iCGM measurements within +/-15 percent of the corresponding blood glucose value must be calculated, and the lower one-sided 95 percent confidence bound must exceed 70 percent. …
Manufactures are not required to publish MARD for SMBG. MARD is not the only metric that should be compared between CGMs. For SMBG it is easy to compare the % within 5,10,15% results in the back of the manual.
Checking SMBG with lab results is a great way to make sure your meter and current test strips are within 20% of the lab result. The comparison is only useful as a pass/fail test. A single data point doesn’t help when comparing CGM to SMBG values.
Hi @savejf. Meters need to meet certain standards for accuracy or they wouldn’t be on the market.
I’ve used OneTouch and Accu-check which were the “big names” a while ago: both brands have various models depending on the “bells and whistles” you want or need. Freestyle and Bayer are also good (yes, Freestyle does make standard meters as well as their CGM). I believe the test strips for a brand will work with all of that brand’s products. There are pharmacy brand meters that may do the job but might not be very durable (IDK) so I would suggest you stick with a more commercial name.
But the key thing may be which meter your insurance covers. And your doctor might have one they prefer.
Now we have strayed off Topic [comparing G7 with Freestyle] and should return to Topic - this might be a good discussion on its own. I’ll just add my acknowledgement.
Chris @spdif I’m aware of extended discussion anout validation standards, a while back NIH published papers on the subject and, I might point out that FDA standard is much more liberal than ISO standards.
Currently American diabetes Association provides description and pictures of more than 75 BGM, currently being marketed, that qualify under FDA 510k clearance. We just need to know the limitations and benefits of devices we use.
The FDA standard linked above acknowledges most meters meet ISO 15197 and describes how the FDA standard is more stringent. When the CGM is wrong and I need a BG level to make a treatment decision a meter that meets either standard will work for me.
@WarriorMom13 I attended the recent DC JDRF conference and spoke with the Dexcom rep who stated Dexcom did NOT have plans to discontinue the G6 this year. He pointed out there are a LOT of people on Omnipod Dash that is not G7 capable, limited compatibility with the Omnipod 5 (currently), and limited capability with Tandem Tslim (only certain versions of the G7). He may have been talking thru his hat, but seemed fairly knowledgeable about it.
I am curious how the G7 starts the warm-up if you don’t “start” it, but rather keep using the expired sensor. And, I wonder if people who use the Tandem pump can do the same as people who don’t use a pump, start a warmup period without actually starting it to send #s to your pump. I have not switched to the G7 yet, but am concerned about this issue. Have any Tandem pump users done this same trick with success. Thanks!
@mkenni , The sensor “starts” - activates the battery and starts, when you apply it. You don’t have to use your pump, you don’t have to use your phone. It warms up and begins sending data in 30 minutes. Now, you can’t see any data unless you go to your phone or pump and start a new sensor. All that does is “Bluetooth pair” the sensor to the device. Once it’s paired, you will see data. If you put the sensor on 4 hours ago, you’ll have all 3-1/2 hours of data on your device. Yes you can do this with the pump too. Just keep on using the old one when you apply the new one and then switch to the new one on the pump.
The actual how? It has to do with the magnet in the applicator. That activates the device. When the magnet is pulled away from the sensor, it turns it on.
Dexcom updated their software so you don’t see double lines anymore. The CGM data on the Dexcom app will show you the new sensor all the way back to warmup . (edit) you can still see double lines!
I just got my first G7, a sample from my doctor’s office. I started it yesterday afternoon while my G6 was still working (I’ve got @ 4 hours left on it now). So far, the G7 has been more accurate compared to finger sticks. For example, my G6 said I was at 108 this morning, while my G7 said I was at 129. A finger stick with my Contour Next meter showed I was 133. Not sure which is actually most accurate of the three though. Any thoughts?
Pam K.
My first thought, Pam @pamcklein is how dud YOU feel - closer to 108 or closer to 133? (Long-timers like you and I can often recognize those differences.) You may have noticed in the Dexcom G7 box-stuffers that the caution suggested when even considering a calibration is to do two finger-sticks, spaced and then compare those two readings with the G7 and weigh the three with what you feel.
My second thought is placement on your body. I did a similar comparrison that you are doing for 6 days and found that at times [not always], the G7 on my arm lagged the G6 on my abdomen - the differences usually closed with the next 5-minute reading. Also, your finger-stick would be earlier to reflect the “dump” of glucose your body gives automatically to get you moving - those wake-up steroids.