Thoughts on current CGMs

I’m currently using Medtronic Guardian 3 CGM with my 670G. I do not use the closed loop. Maybe 1 out of every box does the 7 days. Most last about 5 then get “cranky” and want to be calibrated more frequently or I get “sensor updating” message which can last up to 3 hours.
I’ve received replacements but this is an on going issue and its getting tiring.
They just replaced y transmitter and charger

Has anybody tried the new freestyle one?

I am thinking if switching to Dexcom and have spoken with the area rep.

Before I make any decisions on what to do next I’d like to hear about other experiences with CGMs



1 Like

Hi Anne @Anne98, it is too bad that your sensors do not work properly for the intended period of time. I do know that monitoring sensors do not work for all people - BUT!!!

You said you are not using a “closed loop” system at this time, so I’l ask if you want to eventually move on to a closed loop. I currently do not use a closed loop [my current pump does not have that software] but my plans are to move to a pump that does.

I currently use the DexCom G5 sensor [[up until a few weeks ago the only CGM approved by Medicare] and find the sensor works very well with my old body and they stay in place very firmly for the intended period of 7 days. Actually I have “restarted” a couple and ran them for 10+ days; Medicare required bastardized software in the transmitters and special packaging that only included four 7 day sensors that had to last a full month between reorders - I complained and now get sufficient sensors.
I strongly recommend this G5 sensor and I understand the G6 is much better - I will begin getting the G6 when my transmitter needs replacement. As soon as I can replace my current out-of-warranty pump with a more modern variety I am wanting a Tandem t-Slim x2 with the 2019 “smart software” which fully integrates with the G6 and not only fully controls basal delivery but will also administer bolus corrections as needed.

1 Like

thanks for the input
I tried the closed loop twice
Absolutely a waste of my time and effort
It quickly left me basal deficient and it took me over a week each time to get back on track with out the closed loop
Having said that, Medtronic never offered me any classes or training on the new pump (I did do the on line classes)
I had to seek them out myself
I did the pathway program to get the newer pump as I had been thru 2 530’s over the past year
In hind site, I should have waited out my warranty and used a Dexcom in the meantime
I have only sporadically used sensors over my 40+ years with diabetes
but coming up to the Medicare line in a coupe of years, we thought it best to get a proven track record using a sensor
Without it I can manage A1Cs in the high 6’s but occasionally will tip over into 7
I’ve tried Omni Pod in the past but didn’t care for the PDM
I am considering looking at their new DASH system but its so new, sometimes its better to wait a bit
again, thanks so much for your input


I use the Dexcom 5, sometimes love it, sometimes not. The accuracy is inconsistent.
I also have an Omnipod. I love the lack of a tube, don’t like the 3-day lifespan of the pods and echo Anne in not liking the PDM. But lack of a tube makes it all worth it for me.
What I am looking forward to is Dexcom and Omnipod becoming a closed loop system, which is currently scheduled for 2020. When that happens I’ll try closed loop.

Hi Anne,

I have the 670g and the identical CGM. I use the closed loop 100 percent of the time and have a great experience, as long as you get to know and understand the little quirks of the system. When you first insert a new sensor, the Guardian CGM needs to “marinate” a few hours before it actually starts tracking more tightly to your actual BG. So you need to take this in to account when first starting a new sensor. I too get about five days out of each sensor and realize the same “sensor updating” over several hours. I’ve learned that this is its way of telling me to change-out. I need to recharge the transmitter and replace the sensor. For me, I just know it has a five day shelf life, and not seven, and move on. As far as lack of training, I did have a different experience with a Medtronic coach calling me several times to introduce the product and provide training. You might want to give Medtronic a call and ask for some 1:1 learning and I bet you they would be happy to connect you up. I have always found them to be very responsive and helpful on the phone. Although I have only one experience with a pump and CGM, that with Medtronic, as you can tell, l am a satisfied customer. Good luck to you, Drew

Im curious,
are you paying out of pocket? because if they give you a month (or 3) of supply, and you get only 20 days instead of 30, thats 3 months at the end of the year that you are shortchanged for? does Medtronic send you replacements for the ones that didnt work for 7 days?

Hi Emet,

I have a co-pay tied to my work insurance. They have sent me replacements in the past, although I have not consistently requested.

1 Like

I’ve started calling them on the carpet for the sensors not lasting 7 days.
They have replaced 5 recently for me and one failed after 3 days and it “told me to replace it” It is time consuming to call about it because of all of the questions they ask so you should keep a log.
As far as the closed loop goes I probably didn’t give a fair shot but my thoughts after continuous interrupted sleep and daily activities for a week are: (and I say this with a bit of a smile)
“if my pancreas had to work this hard to keep me going, no wonder it quit”

I use the Freestyle Libre; have had it since the summer. At first I wasn’t too thrilled because it’s obviously not as “techy” as Dexcom or other CGMs – it requires you to scan when you want to know your levels and it does not alert you if you’re low. But, I like it as a person who’s just starting out on this T1D journey, though I don’t know if long-term T1Ds are as keen, based on some snarky comments left on my celebratory post in a Facebook group. It’s handy, though, and relatively affordable, if $75 for three sensors that last 10 days each is affordable for you.

thank you for your input. i was hoping to hear from a Freestyle user. Good to know it doesn’t have any alerts. My guess is that it is geared towards the Type 2 people to get them to follow their glucose levels.
If it works for you as you start this journey, then use it. The technology is changing so fast that it can get overwhelming as to what to try next.

The Dexcom g5 and the new g6 are easily the most accurate CGMs on the market. After a day or two zeroing in, you get a good 14 days of use out of one sensor. HOWEVER, it will not talk to your 670g pump, if that is important to you. To me, the accuracy is more important. The g6 is amazing, NEVER needing calibration once you get a new sensor started.

1 Like

g6 not yet approved by Medicare, from what I heard.

At the moment I’m not impressed with the closed loop(and have tried it several times)
I am hoping to get a Dexcom 6 and if it doesn;t talk to the pump, so be it.
I too would prefer better accuracy .
I think Medtronic has a good product and usually customer service it very good but like everything else,
“if the shoe doesn;t fit quite right, try something else”

I’ve been on Medonic for over 20 years with a few tries at Omni-Pod.
I’m anxious o see how the new OmniPod Dash system works.

Right now I’m just in a bit of a rut…
thank you all for your input and thoughts.

I’m so glad I found this forum

Tandem expects to have their closed loop approved next year sometime in second half of the year. I’m going to get it, because it works with the Dexcom. I will never go back to Medtronic. I think the new 670g closed loop is a dog, based on all the difficulties I see people discuss on diabetes forums. I’m amazed they still haven’t come out with a seriously accurate sensor after all their years of having CGMs. Till then, I use Dexcom g5 and my old Medtronic 530g and wait a year. I was disappointed that OpenAPS doesn’t work with the 530g, or I would build my own system. My issue is at my age, being on Medicare, is they are so damn slow approving something new even after FDA approves it. Their bureaucracy is horrendous. I wish Congress would cut their staffing so they can’t spend so much time being intrusive in our lives.

Hi Anne,
I tried the Medtronic Closed Loop when it first came out and also found it didn’t work for me. I switched from the Enlite sensor to the Dexcom and will not switch back! Even though I’ve read here online that the Gardian is much better, I’ll stick with my Dexcom. I’ve never had a problem with it.

I just ordered a new pump, and decided to try the Tslim X2. Making the switch is scary for me because I’ve only used a Medtronic pump. I’m also excited about it though, because the Tslim works with the Dexcom. I really like the new system they are working on which will adjust the basals. It’s supposed to come out next year. For now, it will suspend if I am dropping, like the Medtronic did. I’m fairly confident it will be more reliable and suspend only when/if I need it, unlike the Medtronic sensor/pump combo.

That’s my opinion. I’ll try to let you know how it goes once I get started on the Tslim!

Pam K
T1D 54 yrs and counting!

Hi Anne, I’m a Libre user since March. I really don’t want the alerts and alarms so this one works great for me. Getting a graph of the last eight hours and trend arrows with every scan helps me stay on top of changes. I went down from a 6.7 to 6.3 A1c. Libre now has the 14 day sensor approved and I was able to get the new reader for it free with a voucher through email from the company. I haven’t gotten the 14 day yet, as I just refilled my 10 day, but going to using only two sensors a month is something I can’t wait for! It’s really only three more days basically than the ten day because that one has a 12 hour warm up verses a one hour warm up on the 14 day. It really is so simple and no hassles to apply and use. Mine stays on just fine the whole time. Always shave the back of your arm beforehand, use both alcohol wipes on the whole area, apply sensor, push gently to make sure it’s all stuck to your skin and scan it with your reader to get it started. So simple!

1 Like

if you take acetametaphine for pain, it keeps the Dexcom 5 from being accurate. I learned that from Dexcom, back when I was using that drug. The inaccuracies went away as soon as I stopped.

Thank you for sharing that information; good to know.

You are correct about Medicare and G6 dexcom-no approval yet.
Also not able to do update on Tandem 2X pump, because you can only use G6 with the pump after the update.

Hi Mary @FlasH2b, CMS has approved the DexCom G6 for Medicare beneficiaries.
All new doctor prescriptions for Dexcom CGM for Medicare beneficiaries are being filled with the G6. Those currently using the G5 will be switched over to the G6 when the beneficiary needs a new transmitter.

The G5 is currently compatible with Tandem t-Slim x2. Software is available for download for both Tandem and DexCom.

CAUTION: Once a DexCom G5 Receiver is updated to G6 use, it can NOT be reversed to G5 use.