What CGM should I choose

My doctor just approved me for a CGM. For a while I've been communicating with Medtronc and they've been helping me out with everything. They just called today and said that they received the approval from my doctor and they're finnishing up the paperwork for the insurance.

My only concern is that my doctor did not suggest the Medtronic because she's expecianced problems with the sensors. She suggested the Dexcom. I've looked into that and I'm highly concidering that one instead. I like the smaller size of the sensor and the fact that they last 7 days instead of 3. My doctor's opinion is also important to me. I'm not sure if I should go with the Medtronic because everything is almost ready to go, or start over again with approval and everything from Dexcom. Any thoughts or oppinions on what CGM you would recommend would be helpfull.

I am also very active and do a lot of backpacking and outdoor activites, so I'm concerned about putting a sensor in a different location than the abdomen. Also with how the different sensors work with water and sweat.



I’m sure you’ll get plenty of varying opinions on this one, but I recommend either the Abbott Freestyle Navigator or the Dexcom. I currently use the Navi, and I have previously used the medtronic.
While it works great for some people, I never had great success w/ the medtronic being very comfortable, and at times it would lose communication signal if the sensor was on one side of my body and the receiver was on the other (and I in no way consider myself “large”).
I have had much better accuracy (and thus more reliability) with the navigator. I have also had much less pain (virtually none) and I also like the auto insertion aspect and “one handed” nature of getting the navigator on my body and up and running. I have also had MUCH less issue with the transmitter and receiver communication. The transmitter piece is larger than both the MM and Dexcom versions, but I think this speaks to its larger antenna (which allows for much better communication between the two devices).
It does require a longer calibration time than the MM or the Dexcom (which is why many go w/ the Dexcom), so that is something to keep in mind. I do not feel that the warm-up period hinders any readings that it gives me in the future though, so I’m fine w/ waiting :slight_smile:
Congrats on getting approval for the CGM, and good luck with choosing one that fits you best!

Avoid the MM CGMS like the plague. Search the forums for more information. You won’t go wrong if you pick the Dexcom 7+ system - the best CGMS on the market today.

I’ll second the opinion on the Dexcom 7+ CGM. I love mine and it has been a Godsend! I am also very active; e.g., hiking, biking, swimming indoors and outdoors, etc. and I’ve never had a problem with sensors since they are so small. I usually adhere mine on my abdominal area, but way over on the side and sometimes just to the rear of my side. I’ve only torn one off during a physical event and it was primarily my fault. Otherwise I forget they are even there and they rarely get in the way of anything. On average, I wear a sensor 14 days, but have gone longer as long as the sensor adhesion is good. Seven day sensor life is the company’s professed days allowed, but they will function much longer in reality. My ninety day supply of sensors will usually last almost six months!

Hi Chrispy: I will second what John said and recommend you NOT get the Medtronic CGM. Mine sits in a drawer. For me, it was wildly inaccurate and very difficult to get a good calibration. I wish I had chosen the Dexcom.

Get what the Ins will pay for. If they will cover the MM go for it. If they will cover the Dex or the Nav you can’t go wrong. The longer insertion time for the Dex is great. The accurace in the Nav is great also. Each has it strengths and weakness. With each you will need to learn the “unique” things about the sensor and software that they don’t tell you about. Be patient when you get it, each will take some getting use to and the will never match the BG all the time.

Enjoy you new experience in to the CGM world.

I have to second Bradford’s evaluation of the Navigator. It’s the only one I’ve used, but I have found it to be accurate and have also found the transmitter and receiver to communicate well - even when I forget and leave the receiver in another room. The 10-hour warm-up for the Navigator is a hassle, but not that big a one. I also agree with S Woodward to never accept any CGM as gospel truth. Any glucometer, including a continuous one, can give bad readings at times. Sometimes a calibration will do the trick and kick it into working as it should. The CGM has given me much more security in how my blood sugars are running - especially overnight. Reading the pattern is the big advantage. In the end, it offers much better control of diabetes.

Hallo, I use the navigator since december last year and in Germany the next generation (version 1.5) is available. The 10-hour warm-up is now changed in a 1-hour warm up! So the navi is a perfect and accurate system. You also can use the sensor much more than 5 days - no problem (15 days and more up to 30).

I would avoid the Navigator. I do agree with the others that it is accurate. I bought mine in Nov. After using it for 11 weeks, it broke. I have been waiting on a replacement now for over 8 weeks and Abbott still can’t say when that will ever happen. Besides receivers being on backorder, people are also waiting on transmitters. They did the same thing for 2 months last year with the transmitters.

I have asked my insurance company to try and get their money back from Abbott and get me the Dexcom. I also filed a complaint with my state’s attorney general because Abbott is not honoring the warranty. I am sitting on sensors that will expire and I have nothing to use them with.

I actually like the Dex better. The alarms are much nicer. The Navigator beeped every 15 minutes if you were out of range. That is great if you were low but it takes longer than 15 minutes to bring a high down. With the Dex, you can set when you want to be reminded.

Someone I talk to on another site uses the Dex and has used hers in her arm without problems. I prefer my arms also and that is where I intend to use the Dex.


I cannot recommend one over the other, but your statement - “I’m not sure if I should go with the Medtronic because everything is almost ready to go, or start over again with approval and everything from Dexcom”, SCREAMS with tell Medtronic to wait!

Fair Winds,

I’ve used both the Medtronic CGMS and the Dexcom 7+, in each case for long enough to give a sensible verdict. In my view the Dexcom is far superior - more accurate and easier to use. I found the Medtronic CGMS infuriating and really hard work. I used to spend ages on the phone to Medtronic trying to get sensors to work properly. The whole thing was just not worthwhile. I changed to the Dexcom 7+ and haven’t looked back. It’s so simple to use and it’s now my constant companion. And here in the UK we have to pay for the sensors ourselves - I wouldn’t spend the money if it wasn’t a significant help to me.

I strongly recommend the Dexcom.


Thanks for all the advice, I called MM and told them to put the order on hold. It looks like I’m going to start the process with Dexcom, as long as my insurance covers it I will be going with that one.

Hi Chrispy,
I just started the Dexcom on the 12th of March…and so far I LOVE it. It has been very accurate for me, and super comfortable. I was concerned about stomach sites as the Sils always bother me a bit…but once the Dex Sensor is in, I can’t feel it.

I did try the MM CGMs last year at a Diabetes event, and while it wasn’t horribly inaccurate…it wasn’t like the Dex for me. I currently use the MM insulin pump…so I could have had the integration.

After only 3 weeks, I can’t imagine not having my Dexcom. It has changed my life that much already. I feel like I have a ‘second eye’, and I no longer sit and wonder what my BG’s are doing at any moment.

If I can complain about one thing with the Dex is the adhesive. My first sensor barely lasted three days stuck on me before I had to put stuff on it.

I highly recommend getting Opsite Flexifix for that.

I recently left Medtronic and went to Dexcom and Animas. My Medtronic sensor started to fail a lot, I had 7 pumps in one year. I know this is not an experience many others have had, but I was really not happy with them. The accuracy on the Dexcom compared to the Medtronic is like night and day. For the Dexcom sensors, I use Mastisol to help it stick for the full 7 days.

All the suggestions are interesting …my observation as a gal from Canada with no other choice available other than MM CGMS …and here is the good news : I have nothing bad to report … been using the system regularly , know how to insert, know how to " wet " the needle , know how to get 8-9 plus days out of one sensor , know where to place " it "( use my legs too ) , know how to set the alarms to help me the best , am very active as an almost 70 year ( old ) senior …my page will attest to that.
All the bes in choosing Chrispy .

I am interested in talking with other uses of the MM CGMS, such as you ,Nel… I have had limited success with the MM system. I like seeing the trends, but I am having a hard time with accurate insertion lately, and being an African -American who hyperpigments with skin trauma, I really do not like the shrapnel scars the javelin-like 9mm insertion needle leaves…And I also have a hard time when I am very busy, “babysitting” the sensor to get accurate calibrations so it fits my lifestyle rather than having to fit my lifestyle to the CGMS. The data, when accurate, is invaluable, but I feel like I have to spin like a top and think about/adjust the CGMS constantly to get accurate data…Are the other CGMS (i.e. Dexcom and Navigator) easier to use and integrate into one’s Life, rather than the one benefit of the MM model , pump integration ? Just curious…
My MM CGMS is sitting in a box with my pump/diabetic supplies. It was getting so frustrating and overwhelming to me, that the MM trainer/nurse told me to leave it alone for a while…

God Bless,


I can’t completely compare, because I didn’t use the MM CGMS long term. However, the short experience I did have, the Dexcom does seem easier to calibrate.

I calibrate twice a day. Once in the morning, and again in the evening (12 hours apart). That seems to be good enough. Sometimes if it seems to be reading a little more off then usual, I may throw in another calibration.

If my memory serves me right, I do remember the MM CGMS asking for calibrations constantly. I don’t feel that way with the Dexcom.

If I had to have gone with the MM CGMS, I would have. I don’t think it is a horrible CGMS.

Hi Brunetta

When I changed to the Dexcom I wasn’t really expecting there to be much difference from the Medtronic CGMS - I just thought it was worth a try. But I was amazed at how different it is. With the Medtronic CGMS I was, like you say, fussing over it constantly. With the Dexcom you just insert it (pretty easy), switch it on and wait for the initial period to elapse (2hours). Then you calibrate (at any time of the day…just calibrate!) with two blood glucose readings, one after the other, then off you go. You don’t really have to worry about it at all after that. You calibrate it a couple of times in each 24 hour period, but you don’t have to consider how stable you are when you calibrate, unlike the Medtronic system. It is completely different and pretty much fuss-free. I’ve had the occasional sensor which just doesn’t work, but these get replaced. Apart from that, after several months of using the Dexcom I’ve really had no problems with it. It’s a bit inconvenient having a separate machine to deal with in addition to my pump, but definitely worth it. Also, the alarms wake me up at night - I used to sleep through the Medtronic alarms!


PS It’s worth adding, and I should have done before, that some people get along with the Medtronic system well. I don’t honestly know how they do this, as I tried very hard with it and couldn’t get it to work for me consistently. Someone I know (who uses the Medtornic CGMS) had a hunch that it may work better if your sugars are normally pretty stable, and maybe that’s true, I have no idea.

Thanks Rosemary, for your comments:

I did not expect that getting on a MM CGMS would be like carring for a fussy, inconsolable infant…No, not that: the fussy, inconsolable infants eventually grow up and sleep through the nght and become mature, needing less complete attention, as they eventually learn to care for themselves… And you love them from the instant you have them in your arms. I wish the MM CGMS would grow up.
I did like the Medtronics CGMS and still do, but I do not love it, like the DEXCOM users seem to. I can be away from the MM CGMS for weeks at a time and not miss the hassle at all… I am not hypo-unaware, and if I test very frequently after a questionable meal, bolus, or before/during extra activity, I can get more accurate data do not need( or want) to have on the MM CGMS.
I wonder if Medtronics is going to revise their product?? I am sure that they have had many complaints along with some who find it wonderful. Like Danielle said, I do not find it “horrible”; and when working properly, it has helped me see some trends in blood sugars so I can more accurately set basals and carb/insulin ratios and sensitivities, a big plus… I just did not want to be a full-time MOM to it.

God Bless,

I see you have noted that the Dexcom sensor lasts 7 days. In fact, most of us get 14 days or more out of each sensor. After 7 days you just issue the command to Stop sensor, then immediately do a Start sensor, and after two hours you are good to go again. If your insurance pays 100 percent of the sensor cost perhaps that doesn’t matter so much to you, but for those of us who have to pay out of pocket it sure makes a difference.