When a person considers using a Continuous Glucose Monitor (CGM), they often ponder their choices. Do they want a Dexcom, a Guardian, a Libre, or another option? In this article, we will compare the Dexcom G6® and Medtronic Guardian™ Connect.
Dexcom G6®
The Dexcom G6® features include:
- approved for use in children 2 years old and older.
- constantly monitors fluctuations in blood sugar based on the interstitial fluid.
- uses Bluetooth technology.
- sensors last 10 days.
- sensors are water-resistant so it is safe to shower with.
- does not require calibration. Users can still choose to enter a calibration if they would like to or feel that the sensor seems inaccurate.
- has a 2-hour warm-up period.
- customizable alerts for high and low blood sugar levels.
- can connect to an app on your phone and send readings directly to the app.
Medtronic Guardian™ Connect
The Medtronic Guardian™ Connect
- approved for use in those 14-years of age and over for the stand-alone Guardian™ Connect and ages 2-years and up when used with an approved Medtronic insulin pump.
- constantly monitors fluctuations in blood sugar based on the interstitial fluid.
- sensors last 7 days.
- calibration must take place within 2 hours after you connect the transmitter to your sensor and start the warm-up period, again within 6 hours (first day of inserting sensor only) and then every 12 hours although calibrating 3-4 times per day is considered optimal by the manufacturer.
- the transmitters (Guardian™ Link and Guardian™ Link 3) are safe for submersion in up to 2.4m for 30 mins.
- customizable alerts for high and low blood sugar levels.
- can connect to an app on your phone and send readings directly to the app.
Which is more accurate, the Dexcom G6® or the Medtronic Guardian™ Connect?
According to Connected in Motion, the Dexcom G6®’s MARD falls between 8.7%-9.4% depending on day of wear (with Day 2 being the most accurate), whereas the Guardian™ Sensor 3 ranges from 8.7% to 10.6% depending on the site you wear your sensor and the number of calibrations (with 4 calibrations per day leading to the greatest/lowest MARD.)
In other words, both systems have similar accuracy levels with the Dexcom G6® being slightly more accurate.
What are their similarities?
Both the Dexcom G6® and the Medtronic Guardian™ Connect…
- have the option to use your phone to monitor readings.
- have some form of alert system that can be set.
- may have adhesive issues that require you to use other sticking overlays.
- have both stand-alone and insulin pump integrated technologies.
- have excellent customer service and replacement policies.
- both are approved for use on abdomen and back of arm.
What the difference between the Medtronic Guardian™ Connect and Dexcom G6®?
Differences between the Medtronic Guardian™ Connect and Dexcom G6® include
- the Dexcom G6® does not require calibration unless there are significant differences between results and symptoms.
- you can make dosing decisions from readings on the Dexcom G6® but not the Medtronic Guardian™ Connect
- The Medtronic transmitter can be continuously reused but must be charged when the battery runs low. The Dexcom transmitter will last 3 months before it should be disposed and a new one used.
Which is better the Dexcom G6® or the Medtronic Guardian™ Connect?
If you are using a Medtronic insulin pump, the Guardian™ systems allow the pumps to fun on “auto-mode”. For people who prefer a Tandem insulin pump or are looking at the DASH, you may prefer to use a Dexcom.
When you look at cost, if you are using a subscription the cost is still quiet par. You will require more Guardian™ sensors than Dexcoms because of the difference in sensor life.
Some users on a recent Reddit thread felt that the need for calibration on the Guardian™ made the Dexcom G6® much more attractive, BUT your diabetes may vary! What is right for you may not be right for your neighbour.
Weigh the pros and cons of all systems before you decide. Educate yourself. Know the features that you require in your device and discuss your options with your diabetes team first before you commit to purchase any system.
Compare CGM Features
Download the free PDF to compare Continuous Glucose Monitors
I have used both, and frankly, there is almost no difference. I really like my Medtronic system. But I also see the benefits of Dexcom. Thank you for the review.
I’d like to know the average daily cost for each sensor (no insurance)? I understand each sensor has a different life span.
I’d like to know the number of sensor users each company lists (estimated is fine)? Differentiated counts by type 1 vs type 2 would add more value.
How much does Joe Jonas make promoting Dexcom ($/stock)?
I originally started with the Medtronic 670G but switched over to the Tandem t-Slim pump because Dexcom rules the market when it comes to CGM. That being said, I now regret wholeheartedly going off the Medtronic pump. The ONLY reason I did so was due to Dexcom. The Tandem pump is absolutely the WORST pump EVER! I keep telling their reps that it must’ve been a non-diabetic who designed the pump because of all the things it lacks…The ability to tailor the alerts/alarms to SILENT mode. The non-display on the main screen of when insulin was given. The lack of a TEMP mode, which leads to you forgetting to rest the pump back to normal mode. The inability to properly adjust the insulin as well as the Medtronic pump. And my favorite…The constant, CONSTANT bothering of you with inaccurate alerts. “No activity for the past 12 hours” when I just checked the main screen. 3 different alerts within 60 seconds…all reporting a prediction of high blood sugar. And my favorite (no kidding I actually get these quite often)…Low blood sugar detected 10 HOURS AGO!!!! Gee…Thanks for letting me know why I ended up in the hospital.
As I stated…Do NOT go with the Tandem pump unless you want to be contantly bothered with alerts or you are too lazy to take your blood sugar 4 times a day. I thought I was too lazy, but now realize that it is more work to use the Tandem pump with less success than it would’ve been to stay with the Medtronic pump and take the 4 tests a day and swap the battery.
Totally agree. My trial with the Tandem tslim was a horrible experience
I have used both CGM systems, Medtronic and Dexcom. The most annoying thing about the Medtronic CGM is all to the required calibrations. I was told by my former endocrinologists to test 4 times per day, however, using the Medtronic CGM I was having to prick my finger 4 to 8 times per day. It was horrible. The only thing they got right was the rechargeable transmitter that could be used over and over again.
Since I switched to Dexcom’s G6 CGM seven months ago at this point, I have pricked my finger just two times. My fingers feel better than ever, the relief is amazing. The accuracy is superior to Medtronic’s system too. There is no comparison, Dexcom wins.
I do love my Medtronic pump, however, I do believe they make the best insulin pump out there. The t-Slim pump causes pain during boluses too often due to the piston mechanism. I am also not bothered by having a design with a tube so not interested in the tubeless pump. So, I am still using a Medtronic 670G and a Dexcom CGM without a highly desired closed loop function.
I was excited to hear about Medtronic “collaborating” to be able to use other CGMs with the Medtronic pumps, however, that was announced THREE YEARS AGO WITHOUT ANY FURTHER UPDATES. I don’t want to switch to a different pump, but, Medtronic is pushing my buttons.
Just wondering how you know your G6 is accurate if you have only pricked your finger 2 times in the 7 months you have been using it? What are you basing your comparison on? I recently wore a Medtronic and Dexcom sensor at the same time and found there to be virtually no difference in accuracy between the 2 systems and my blood glucose meter. Dexcom was out by a reasonable margin about 5 days in but I calibrated and that got it back on track. I would love to be able to trust it’s accuracy and not ever test, but realistically I think that is a big risk to take. I would rather have the peace of mind of testing a couple of times a day just to be safe. I have been using Medtronic for 3 years and have been reasonably happy with it. It’s sensors fail early at times and sometimes asks for 6 hourly calibrations towards the end of a sensor session which is very annoying. I’ve only trialled a couple of Dexcom sensors so do not have enough experience with it to say if it has similar issues. I can say I much prefer the Medtronic app and if it could be combined with the G6 device/sensor it would be a perfect combination.
The calibration of the Medtronic sensor was the worst, and if it fails twice you have to insert a new one. So then I’m out a sensor set. Medtronic is good about replacing items when they fail but it’s such a pain. Dexcom has been so much nicer. I occasionally finger test to check the accuracy and it’s generally right in line. Only once recently did I need to calibrate and that was because it kept reading 40 after I put a new one in. After calibrating to the correct glucose level it corrected itself no problem.
I like my Medtronic pump but their sensor leaves a lot to be desired compared to Dexcom. I’m going to look into omnipods next year since those communicate with Dexcom sensors.
I switched to the Tandem pump (which works just as well as Medtronic for me and actually keeps my overnight and morning sugars flatlined on graph better than Medtronic) simply because I wear my sensors on the back of my arms and it was impossible inserting and taping with 1 hand. So much tape! Plus I had an injury and need regular acetaminophen dosing during the day which was throwing my numbers off (it affects Medtronic’s sensors). For Medtronic to tandem, if interested in my experience, I find the pump smaller, I use sleep mode 24/7 so it keeps me at 6.1 not 6.8. I am comfortable now with trusting dexcom with periodic checks so not calibrating continuously is fabulous. The only thing I didn’t care for but am used to now is filling the reservoir because I can’t see inside it (are there air bubbles?) and I did have to switch from fiasp to novorapid. I’ve been a T1 for over 50 years, so switching insulin again wasn’t a big deal, just give me insulin! There wasn’t much of a difference and I’m fine with any fast acting. If the Libre was used by a pump that had an automode/control IQ, I’d most likely be fine with that, they are small and flatter.
When is it going to be available the Guardian 4 (no calibrations needed!))?
IT’s been all around the world for almost 2 years, and here in the US we’re stuck with the 3 🙁
Sadly, it is often a matter of meeting regulatory requirements in the various countries that can cause a delay.
I have never used anything other than Medtronic, which I have been using for over 20 years. I started using the CGM when it became available, but it has always been very unreliable. One thing that often caused problems was in bed. Sleeping in any position other than on my back would often cause incorrect low alerts, anything that smothered the sensor or pump (or even just being under the covers and not smothering it, it’s almost like it needs to breath more than air than me) would result in a false low, and within 10 minutes or so after getting out of bed it would come back to (supposedly correct) numbers, but this sometimes caused Sensor Updating messages and other problems, which coming back from was often unlikely or inaccurate, forcing me to put in a new sensor (which we all know is frustrating). This ended up in needing more sensors than Medicare wanted, and I would end up needing to go through a lot with them). Many people have said that the other companies have better sensors, but they do not have Auto Mode, which is very important to me because I have an extremely inconsistent schedule. I have heard that Dexcom recently added a closed loop system (Auto Mode) to their products. I don’t mind having a tube instead of a tubeless pump, and I am willing to do calibrations (as long as they are not overly frequent and result in accurate CGM numbers), what I do mind is frequent (sometimes incorrect) errors and inaccurate numbers. After hearing that there was a closed loop system other than Medtronic, I wasn’t sure how to feel. Has anyone used the closed loop system for Dexcom? Is it reliable enough to be worth switching?
I had been using Minimed pumps for almost 35 years when I switched to the T:Slim recently. My last Minimed was the 670G and the Guardian 3 sensor and Auto-Mode. I found the Minimed solution to be incredibly annoying for the following reasons:
1) It required 2 calibrations per day.
2) Sometimes the calibration was not accepted and you had to wait 15 minutes to try again. Not a huge deal unless you tend to calibrate before going to bed as I do.
3) The 670G Auto-mode could only adjust basal. No correction boluses but that has been fixed in the new 780G.
4) Pump alarms were annoying. They went from the basic alarm to “screaming” in less than 10 minutes. If you’re driving and can’t
pull over for a few mins you have to listen to that racket continuously.
5) The process of installing the sensor was unreliable. Sometimes you’d have to take the transmitter off, place it back on the charger then put it back on and try again.
6) It exits auto-mode too easily and you have to perform a finger-stick to get it back into Auto-Mode.
7) It did not do a great job of controlling my BS.
The proof’s in the numbers though….My A1C went from 7.8 to 6.5 after 3 months of using the T:Slim. My BS is much more stable.
Alarms not nearly as annoying. No calibration required. It takes way less maintenance overall. The sensor lasts 10 days and don’t require calibration so you mostly forget about it.
Nothing’s perfect though. Here are a few issues I have found with the T:Slim.
1) It has an “activity” mode to allow your BS to run a little higher when exercising. It does not automatically turn off after a certain number of hours though and it’s easy to forget.
2) Filling the delivery tube takes much longer than the Minimed.
3) The time between high BG alarms is too short.
4) Depending on which infusion set you use it’s a little harder to disconnect temporarily.
5) The screen is a bit more fragile and scratches easily.
6) When you’re done controlling the pump and place it back in your pocket it’s too easy to accidentally hit the bolus button. It’s not that you get a bolus but it warns you that the bolus was not completed even though you never intended to start a bolus.
I think that the new 780G is probably a big advancement over the previous generation and hopefully people have a good experience with it.
At this point I have committed to my switch to T:Slim and am very happy with it so no plans to switch back.
I am 78 years old, have been a type 1 diabetic for 50 yrs. I did 4 injections per day for 35 yrs, started using Medtronic pump 15 yrs ago. The one complaint about Medtronic pump is , too big, too heavy. It takes a AA battery which makes it heavier. It seems every time they come out with a new version, it’s bigger! Bigger is not better.
I tried Medtronic sensors, not impressed. I currently use Dexcomg6, which I have no copay with insurance.
I agree with other users, these devices have too many alerts, many of us do not need. I have been woken up too many times at 2am!
I have been using the Dexcom G6 for about 3 years. I find it to be very inaccurate. I still check my blood glucose about 5 times a days because I do not trust the G6 readings. I have to re-calibrate 3-5 times a day. When I was in the study and voiced my concern over the readings I was told to remember they were about 5 minutes behind a manual blood glucose reading. My blood sugars have always been up and down so I take accuracy very seriously. I have started re-calibrating when the D6 readings are at least 10 mg off from an actual blood glucose reading for fear of getting too much or too little insulin. Even a couple of units off can be troublesome. Note, there has been several times that the readings were 40 or more off. I have been awaken in the middle of the night with a falling rate alert only to check and it was within normal range. I keep using the CGM because I longer am awakened when my blood sugar is low. I wonder for those of you that claim it is accurate, what is the range that you consider it not to be accurate.