Tandem + Dexcom vs. Medtronic

For 22 years I used Medtronic / Minimed. I always upgraded to the latest model. After a visit to Cleveland Clinic I decided to take the Endos advice a switch to Dexcom and Tandem.

WOW! This is night and day to Medtronic. I go weeks without finger sticks. Sensor good for 10 days with little to no irritation, exercise and sleep mode is amazing. Most important in range (80-180) 90% of the time. Easy to manage because the software is easily accessible and on my phone.

I am not paid by these companies just a user who know a better solution in the market. Why people are leaving Medtronic who bought a great company, Minimed +20 years ago and didn’t invest.


I switched too. I think the biggest issue is the reliability of the sensors.
The Medtronic pumps are good pumps. If they would allow dexcom to control them,I think it would be a real contender.
As it is now , Tandem/ dexcom works best.


I have also used Medtronic/Minimed since I started pumping 22 years ago. I had a horrible time with their sensors. The amount of stress and frustration they caused me made me just stop using sensors altogether.

Based on what I have read on this forum, I decided to give dexcom a try. Im only on my second sensor, but, as you said, it’s like night and day! My Medtronic pump is now out of warranty so I think I will be switching to Tandem.

I would agree with @Timothy that people have left Medtronic because of their sensors. I was a very happy Medtronic pumper but had an horrendous experience with SofSensors. When I switched to Dexcom 7+ if was like a miracle that the sensor trends were always accurate and the readings were mostly accurate. When I chose my next pump, I chose Animas because they were on tract to integrate with Dexcom G4 sensors. That integration was ultimately under-whelming but I have never considered leaving Dexcom. I think that MedT’s Guardian sensors are accurate for many people, but they are finicky and require lots of tape and calibrations. I don’t love my Tandem pump but it is my only choice now. I won’t give up Dexcom integration with my pump and I had a very bad experience with Omnipod. It is sad how we have many fewer pump choices than in the past.

Ditto for me. We called them the harpoon serters. At least they did improve on that with Guardian, and the rechargeable transmitter was nice.

I also switched to Dexcom Seven, after searching for help on sof-sensors (isig), and found this site with info on dexcom. My endo had never mentioned an alternative when I had complained about sof-sensor.

Now using Tandem with G6, as of this year, having used dexcom+medtronic for 20 years.


I would say right now (tandem/dexcom) is the best commercially available solution. I was also a loyal medtronic customer, but the Dexcom integration along with the tandem product roadmap along with ability to deliver on that roadmap pushed me to Tandem.


Thank all of you for sharing your experiences. Even though I’m and old duffer, my first CGM was a G4 and then, a couple of years later, my first pump was a Tandem. I am REALLY happy with the G6 plus C-IQ combination … but really have no other relevant experience. I feel I always learn something from those of you have lived with multiple CGM and/or pump systems.

Thank you for sharing this with the rest of us.

Stay safe!


1 Like

No surprise I am thrilled with the Medtronic 670g and look forward in a few days to upgrading to the 770g. I support each of us finding our own best solution. . I am glad when that is found for anyone.

I am a Medtronic ambassador. My opinions are my own. They did not pay me to say nice things. OK, they sent me a shirt and a cup but even I am more expensive than that.


This isn’t about preference this is technology. You clearly have not used Dexcom or Tandam. There is a reason the CEO of Medtronic said they have work to do and we’re behind see article https://www.medtechdive.com/news/dexcom-talks-up-type-2-market-medtronic-plays-catchup-in-diabetes-tech-at/570431/

While everyone should have the ability to provide their opinion you should have experience on other platforms. The algorithm is not good and is why Medtronic is losing market share. You must be getting paid by Medtronic.

Same for me. I’ve used two different medtronic pumps prior to tslim this year. Medtronic sensors are terrible. In hindsight, I should have asked them for my money back for my link 1 and 2 transmitters and sensors - it was the worst value investment I ever made. I still had sensors left that I paid out of pocket that I didn’t use because they were stressing me out so much because of the inaccuracies. When i called support, they made it sound like it was only me having these problems and I was the “one off” case that didn’t work so I just thought it was my bad luck. It was only this year that I realised so many others were in the same boat. The medtronic pump good and comparable to the tslim I think however, tslim I think is more forward thinking.

It saddens me that medtronic is still the major player in the australian market. When I had to choose my new pump, I had my mind set on the tslim but my DE tried to convince me to go medtronic. I think they are trained and have more support from medtronic so they are more comfortable with that pump. She also gave me the impression the generation 3 of the medtronic sensors were close to flawless. Thanks to this forum I did my research and found that people are still complaining about their medtronic sensor so it was an obvious “no go” for me. I’m so glad I stuck with my decision to go tslim. Dexcom is way more accurate.


I am defiantly not thrilled with the MedT Guardian 3 sensor - finicky during first 12 hours and too many calibration/BG required alarms. However, I tend to sometimes go high while sleeping atnight and I like the auto mode feature that increases Basil rate while sleeping. I also tend to go low if I exercise more than normal and auto mode stops infusing Basil to prevent excess lows.

Will Tandem/Dexcom accommodate these situations?


Yes, I believe that Dexcom/Tandem can do what you are looking for … probably after some fine tuning.

Here is a handy one-page summary of how Control-IQ works in “normal”, Exercise, and Sleep modes:


Stay safe!



I suggest you read my entire post. I am delighted to have disagreed with, however as I say I am glad for each to have their own choice. As my post outlines, I am not paid by Medtronic. (I do like the shirt.)

I suggest you not sling disparaging remarks in these forums.

1 Like

There are two features I find the most valuable set in Activity mode. Sleep and exercise work great.

Sleep mode I set for everyday from 11-5, moving my blood sugar target lower, it has totally cured my dawn effect.

Exercise - is much like Medtronic moved up your target BG while in exercise mode

Rick - if you don’t have experience with anything other then Medtronic you are giving people the wrong advice on the product. I thought as you did the 670g was good. Clevland Clinic (Cleveland Location) the top hospital in the US / world had the head endo come in during my appointment and tell me you need to consider Dexcom / Tandem. I wasn’t seeking advice or a change. In addition look at the link I provided, The CEO said They were behind.

I have been on Dexcom and never had a false reading, can you say that about the Medtronic sensor. I can bet you can’t say that this week. Night and day difference in the product. You should switch

1 Like

i have used the g5 and g6 , I enjoyed using them as well, and found the difference negligible, Incidentally with both being off and dead on. Honestly I am not trying to change your mind,

Once again i am glad you have found the technology you like.

Rick - Did you use Dexcom with Tandem because the Medtronic only works with Medtronic sensors.

1 Like

I stopped using Medtronic sensors and stated using Dexcom sensors with a Medtronic pump at while using the 530g pump. I did this for a little over two years.

When it was time to upgrade my pump I looked at both tandem and Medtronic products. I chose Medtronic because at the time the financial health of tandem was less than assured. With that choice I was able to get in line for a 670G and later upgraded using the guardian 3 sensor. I used the G5 and later the G6 at the same time for a month. I found almost no difference in performance. Statistically the two sensors were equally close and equally far off blood sugar sticks for the 60 days i used both at the same time.

I also have to use the Free Style sensor for several days each four months. I find it is also roughly the same, once it is stabilized.

I also like the Eversense CGM for ease of use.

Note: I am a Medtronic ambassador. My opinions are my own. They did not pay me to say nice things. OK, they sent me a shirt and a cup but even I am more expensive than that.


I also switched from Medtronic/Minimed after many, many years with them. Their pumps are work horses. In the over 25 years with them, I had 3 pumps. They just last forever! I never saw a need to change. Which was one reason I made a change. There wasn’t a big difference any time I made a change. The sensors were not great. I always gave up on them due to how many false alarms there was. And for away I had Medtronic pump with Dexcom sensor, which worked very well for me. Their customer service was always great, although I never really had to call them with issues. I mean, the pumps just work! I am still a fan of the durability of these pumps!
But I made the switch because I wanted less work. After all these years, I want less thinking about my diabetes. And I must say, my new system is easy and I literally can go all day without thinking about my diabetes. Thee are days that I can go 12+ hours without eating, so it’s cool that I don’t need to think about it. I wanted easy and got it now. I also like the fact that as the company comes up with new upgrades, I don’t need to wait for warranty to expire, I can download the new program and keep the same pump.
I will say, just because I like my Tandem, doesn’t mean it’s the best fit for everyone. Picking a pump is a big deal. You need to think about what you really love about your current system and what you hate about it. And you really need to get your hands on one and play with it. Hear the alarms, see about doing a new site change, batteries vs chargeable, computer & phone compatibility. So much to think about. No one pump makes everyone happy. Every pump I have had has something I didn’t like but you gotta think about what is a deal breaker! For me right now in my life is ease. I want easy, which is why I didn’t go the looping route. Too much work.
So glad everyone likes their pump but there are things I like about Medtronic and Omnipod and things I didn’t like. Gotta pick what are the deal breakers!


I could have written your post myself I agree with every word of it. My one addition is that I sleep great with the tandem IQ whereas before I was taking insulin or eating food almost every night but no longer. And now I am using sleep mode 24 hours a day and by cutting down on carbs I don’t have to think about my blood sugar readings much at all.

1 Like