Swithing from Medtronic cgm to Dexcom


I have been with Medtronic/Minimed right from the start, over 25 years ago when I got my first pump. I have been using the cgm since Aug 2009. It has always varied so much for me, not being able to alert me to highs and lows quick enough. Example, system told me I was 168 with 1 down arrow, I felt awful, very confused etc, did a finger stick and meter said I was 36, which was pretty accurate as I was in quite an insulin reaction.

My Dr has suggested I try the Dexcom system. I have received it and am ready to start, but am heistant. It all sounds good, I’m just wishing it could “talk” with my pump like what I am used to now.

Please give me your pro and cons. Do you Love it?
Has anyone else switched from Medtronic to Dexcom?
IS it more accurate?


We have VERY little use with both Medtronic and Dexcom BUT I can tell you our experience and hopefully it will help you feel good about moving to the Dexcom. :slight_smile:

My daughter is seven years old. We did a trial with the Medtronic CGM about a month ago and it was pretty much a waste of time in my opinion in that it really didn’t give me any more information about her trends than we already knew and it was a painful, annoying experience for my daughter. I found in our three days of the trial that the device was very unpredictable on it’s accuracy and her site was bothersome to her.

For many reasons I still want a CGM on my daughter most of the time. So…even though we couldn’t trial the Dex (not FDA approved for children) I ordered up the Dexcom for us in hopes it would be a better experience. I inserted the sensor on my own this last Thursday afternoon with zero live training (just watched a few video clips on You Tube). It took about 24 hours to be consistently amazingly accurate and has only been off of her meter at most by 7 points since the initial 24 hour period from insertion. The sensor site has not had one problem for my daughter, she hasn’t even mentioned it bothering her in any way (the Medtronic site really bugged her for some reason). The Dex has alerted us to three lows that otherwise would have taken more time for us to discover, one while she was asleep, another while she was at school (25 mintues post checking her with a meter) and one yesterday evening while she was playing outside. Tonight it has helped us to correct a high earlier on in the evening which prior to the Dex I would have been up all night worried about the fact that I had given her extra fast acting insulin so late when I didn’t know exactly when the long acting was going to kick-in. My daughter is not on a pump yet…that will be within the month!

So there ya go - like I said we have very little experience with either CGM but right now I couldn’t be happier with the Dex.

Good luck to you!!

I am a loyal MM pumper. I switched from the MM CGM to Dex soon after trying the MM. The differences for me were significant. The Dex is comfortable to wear, easy to get used to having the extra device and the 2 weeks is a pleasure. I did have itching issues , frustrating times for sure with alarms, and ???, but for the most part…its fantastic!

This site will answer any and all questions you have.

Good luck.

Thank you Naomi’s Mommy, It is Great to hear that it is working well for Naomi and giving you more peace of mind. I am going to give this a try. It has to be better than what I’m doing now.

i have never used the medtronic CGM, although I use their pump. I have the same problems with the Dex that you have with the medtronic. My receiver said 113, i didn’t feel well and checked with a fingerstick, BS 50. then as my sugar went up the receiver continued to say I was going down, even though the numbers on the receiver were getting bigger. That is just poor programming. Then the next day, my receiver said 126, but I had eaten and did not bolus, BS was 235. I took off the itchy thing. I liked having the instant numbers, but they only seem to be accurate when I am in range, and that isn’t when I need help.

Hi Lisa, thank you for your response. It’s nice to hear from a MM pumper. I’m really excited about the Dex, especially that it will be more comfortable to wear and ACCURACY!

Ride the frustrations…they will occur, but when it works…it makes life eaiser for sure.

We haven’t personally, but I know five adults who all wear the MM and switched to the Dexcom for a better CGM experience. One of them is my son’s psychologist at the Endo’s office. That’s 100% of the adults I know who use the MM (except for one who just gave up on the CGM all together.) We are very happy with Dexcom - it seems to catch lows at about the same time my son feels them - because of the lag we have it set to alarm at anything below 80. If it alarms he’s usually around 60-65 if he’s falling quickly. At nighttime when his bgs aren’t moving as quickly it’s even more accurate so we’re happy with it.

Hi Teresa, I think that it is very rare that someone gets such inaccurate numbers on the Dexcom. One thing that can be a problem is that you may not be well hydrated and that can affect readings. Not sure how long you have had the Dexcom, but this also may have been a faulty sensor or even receiver. Did you try calling Dexcom to see what they had to say? It is amazing for my daughter and I can’t imagine life without it now. Before this she used the Navigator and that was also very accurate, but the Dexcom is a better fit for us.

I have used both - I did not trust the Medtronic… I do trust my Dexcom 100%. Also, the company is great on support - just call them anytime 7/24 - they will answer your questions. For me, here are the key advantages - the Dexcom 7 Plus accurately tracks the TRENDS of your BG levels - I know if I am going up or down and how quickly. I am able to quickly and reliably make adjustments to assure my BG levels are as flat as possible without too much work. Like everything, it will take a bit of work and familiarity before oyu are as comfortable as I am with the device, but it will happen soon, I am confident.


Thank you Everyone for your replies. I am connecting to Dex tomorrow, have had too much going on this weekend to try it any sooner. All I know for sure is the MM system just isn’t accurate enough and from what I’ve heard for all of you and my Dr, for the most part, the Dex is. I need to be able to trust my system.

We used MM cgms for 3 years, then switched recently to Dex. Night and Day difference. Love, love love the dex and would not go back!!! Bottom line is I trust Dex, it is so much more accurate for us. I had enough random crazy readings with MM that I started questioning almost all of the readings. The Dex is so much easier to insert (no guessing on the angle, no fear of losing the transmitter and trying to tape it to death). It’s less painful to insert and more comfortable to wear, has longer wear time and simple easy to use interface. My only regret is that we didn’t make the switch a long time ago!!! You will be very pleased.

Hi Jacki. I hope you will be as pleased as I have been. Began w/MM, combined nice feature. Night and day difference, I stopped using the MM CGM as the results were just horrible, more so into the second year of use. Once you figure out the best way to get Dex to work for you, I will bet you too will be glad you changed. There is still a delay on both falls and rises, the Dex is not to happy when your sugars change rapidly in either direction but be patient and it catches up; you may find inserting anywhere from 4 hours to the night before you start the sensor will prevent those dreaded ??? that have a tendency to occur at the begenning, many find the first 24 to 36 hours of use with the Dex the numbers are a little off, but most of the postings I have read and for me too, after the second day it is pretty accurate. Usually 2 weeks is good for one sensor, I find it begins to miss my highs more so at the end of the second week, but will still catch the lows. Will not go back to the MM CGM - i did not miss not having the MM CGM on, I do miss the Dex when I take a day or two breather because the accuracy is so good!

Yea, so far so good. Insertion was Awesome! No matter what, mm always hurt and would bleed often. Just did a bg test to confirm, Dex is right on target! Yea!

Ok, I just realized I can’t program a dual wave bolus into the Dex. How do you handle this? I put the whole amount in for my lunch, but it’s not true since 1/2 is now and 1/2 over the next 1 1/2 hours.

I just enter the total amount of a combo bolus into dex if I’m using the events.