Dexcom G5: Not just a matter of convenience

//Dexcom G5: Not just a matter of convenience

by Gary Scheiner MS, CDE
Dexcom’s recent release of their G5 system introduces a number of opportunities and a few challenges for people with diabetes, as well as those who care for and treat them. G5, for those who don’t know, is the same as Dexcom’s previous G4 but without the need for a receiver: The transmitter emits a bluetooth signal that is picked up by a cell phone, and an application installed on the phone displays the data and emits alerts and warnings. To be honest, not all that much has changed. The sensors are the same. The accuracy is the same. The trendgraph displays and alert settings are the same. Calibrations are still required a few times a day, and a “share” option exists for those wanting others to “follow” their data.

Sure, it’s nice not having to schlep around a separate receiver to display the Dexcom CGM info, although G5 does come with a receiver for those who choose to use it in addition to or instead of the cellphone app. Having used G5 for a couple of months now (Dexcom sent me a pre-release version to study), I have found a number of advantages and disadvantages to the new system:

Dexcom's recent release of their G5 system
Dexcom G5 PROS

No receiver to misplace or lose. I’m much less likely to lose my cell phone than a CGM receiver. I used to pay my kids $5 to find my lost Dexcom receiver, which happened regularly. Then someone suggested they might be hiding it on purpose just to make 5 bucks.

The trendgraph screens allow you to scroll your finger over the graph and see the individual BG values and event entries.

Instead of the usual boring alert beeps, the system allows you to choose from 22 different types of tones for each type of alert… including the sound of a baby crying, a police siren, or a dance beat. Fun!

dexcom g5 mobile high and low alerts

The trendgraph display is considerably larger (about 4X the size of the Dexcom G4 display, and 5X the size of the Medtronic 530G display).

The Y-axis scale can be set to top out at 300 or 400 mg/dl. For those who don’t go very high, the 300 mg/dl max gives the graph greater resolution.

Because numerical values are typed in rather than scrolled in, it takes less time to enter calibrations and events.

Because the display is essentially your cellphone display, the screen can be set to stay on for as long or short a time interval as you prefer. While working out, I tend to keep my screen on constantly so that I don’t have to press any buttons to see my glucose level.

The app has a built-in user guide that includes some nice video tutorials, a setup wizard, and direct links to Dexcom for tech support.

Dexcom G5 CONS

Currently, the program only works with an iPhone. Plans are underway to create an app for Android systems, but it will be several months before this is available. It also does not yet sync with the Apple Watch.

The transmitter is slightly larger (thicker) due to the blue-tooth component.

Personally, I found the bluetooth transmitter range to be about five to ten feet less than that of the radio transmitter.

The new transmitter battery life is about half that of the old transmitter. It really will only last for 3 months. You will get a warning prior to its end of life, and it won’t go more than a few more days beyond this before it is finished. Not like the G4. So, I would say that the lifetime is 3 months and the user will need to re-order on time. Put a note on the calendar, or a reminder in your phone about a week before that 3 month date to ensure you get a new transmitter all ready to go.

Although there is no separate receiver to charge (unless you choose to use it), most cellphones require charging on a daily basis. And if the phone dies, so does the CGM display.

In many social situations, looking at one’s phone is considered rude or a sign of boredom or disrespect. It is necessary to look at one’s phone to see the CGM data, unless one uses an iWatch or resorts to using the receiver that comes with the G5 transmitter.


Extracting data from the G5 cellphone app is still a work in progress. Dexcom’s “Clarity” software, once up and running, will not have the ability to merge sensor and pump (or meter) data into the same reports… at least not easily.

G5 cellphone app

MY WISH LIST for the Dexcom G5

It would be nice if the G5 app could play customized music based on where my blood sugar is (Jackson Brown’s “Running on Empty” when I’m dropping, Billy Joel’s “I Go To Extremes” when I’m very high, etc…). But realistically, even without having to make costly hardware/software alterations, Dexcom could have easily made some nice improvements to the system. Here are a few simple (and low-cost) changes I would have liked to see:

  1. Data statistics: Generate numerical “scores” on a daily basis, showing average BG, standard deviation, and percentage of time above, below and within target range. This serves as a nice motivator.
  2. More history: Allow scrolling back to previous days’ 24-hour trendgraphs for detection of recurrent patterns.
  3. Customizable alert times: Many people prefer to have more (or less) aggressive high/low thresholds at certain times of day. For example, higher “high alerts” are often desired overnight to allow uninterrupted sleep.
  4. Fix the repeat alerts for wavering glucose! When glucose hovers around one’s high or low threshold, the same alert can occur repeatedly… even if the snooze feature is enabled. The system should be able to recognize when the same alert last took place and block repeats.

There you have it. G5 is clearly a step in the right direction for people with diabetes. Not perfect, but a definite improvement. Compared to G4, it may not radically change the way we manage glucose levels, but it certainly improves the ease and quality of life for people with diabetes. And that’s enough for me!

By |2016-12-08T23:26:47+00:00October 9th, 2015|Thinking Like A Pancreas Blog|18 Comments

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  1. Mike September 14, 2016 at 9:32 pm - Reply

    I am a type 1 diabetic since age 11. I am now 61. I have much experience with this disease.

    I’ve used the Dexcom G4 and G5 products for about two years. As a type 1 diabetic, you should be aware of a few issues that could result in danger. First of all, the product is cutting edge but there are some major problems.

    When used alone with the iPhone 6, there is continual signal loss. I woke up more than twice with critical insulin reactions. And they resulted in injury. The problem is the signal loss. You can roll over on the transmitter (if located on stomach or wherever) and the signal is lost. I have seen signal loss many times during the day for no reason at all. This is when used (Transmitter and iPhone).

    After serious reactions in the middle of the night, I decided to use the G5 Receiver it comes with (as a backup). Since I’ve started this I still have signal loss on the iPhone, but find the G5 Receiver more dependable. The both live together on my night stand at bedtime with alarms on.

    I recommend using both the iPhone with the G5 Receiver as a backup. This will not guarantee signal loss, but when the iPhone is not receiving a signal, the G5 Receiver usually reads the signal but not always 100%. But it is more dependable.

    I hope this can be fixed. I like the product but it needs work to be used with the iPhone alone.

    • Jane cerullo June 6, 2018 at 6:13 pm - Reply

      Thank you!! I am type 1 LADA for about 14 years. My A1c is below 6. Because I test 10 times a day. I am getting tired of poking so much. A pharmacist friend diswayed me from the Libre. She claims it is not accurate and tends to fall off the arm. Gravitating towards the dexcom I had a CGM years ago but it only lasted 3 days and was very large. A couple of thi gs have happened recently including a low when out paddle boarding without supplies my bad. Anyway will discuss with my Endo next month and your post made me understand the pros and cons. Again. Thank you

      • alicia downs June 18, 2018 at 5:52 pm - Reply

        If making the leap to CGM I’d recommend going for the G6! it just started shipping in wide distributin in the US.

  2. Lew October 6, 2016 at 2:17 am - Reply

    now why only iphone ??
    No interest in no availability for Android users.

    Pls suggest another company that has enough confidence in its product to level the playing field to all in need.
    Appreciate your response…

  3. George zoller October 13, 2016 at 9:23 pm - Reply

    Gary how often must you put the sensor on , once every three months? Can you shower with it
    George zoller
    PS my problem is due to liver disease I get no warning of lows

  4. Sylvana Taylor December 31, 2016 at 11:41 am - Reply

    Good suggestions. Omnipod has all those features for 12 years. Not having the app on Android is inexcusable and suspicious.

  5. Sandy January 1, 2017 at 9:26 pm - Reply

    Thank you so much for informing us on your findings. It was so helpful. I have had diabetes for 43 year and have seen things come and go. From your very astute and educated finds i will be waiting for theDexcom Emaginers to put their thinking caps on alittle tighter and do some more improvements before I jump on the band wagon.

  6. ken M stracker January 17, 2017 at 11:50 pm - Reply

    How long can you leave the sensor in

  7. Derek March 8, 2017 at 8:51 am - Reply

    Ive been speaking with Dexcom for some time now about the new G5 and I asked them why they’re is no app for Android yet, and the answer was that one is coming but it is 6 months to year away. The reason they said they only have one for iPhone is that the programming is easier and it seams like there are more iPhones on the market, I’m not programer and couldn’t tell if he was feeding me line or what, but seams some what legit. A Android app is coming.

  8. MIke March 9, 2017 at 5:43 pm - Reply

    Very insightful. I was diagnosed with type 1 diabetes when I was 11 and am now 45. I have used an insulin pump for years and have used both e minimed CGM and am now using the Dexcom.
    Pros of the minimed CGM over the Dexcom are that I have noticed with the minimed are being significantly smaller (thinner) and less abrupt (more like a rolling hill then a mountain) at the site location this seems to help with the feeling of it easily being ripped off during activities.
    The cons of the minimed CGM over the Dexcom in my opinion is that Dexcom does not charge for the use of there app where minimed charges $299.00 and using bluetooth with my iPhone 7 seems to have a much better signal quailty with significantly less lost signals in the middle of the night or actually anytime for that matter.
    My personal opinion is that minimed has better education regarding the CGM. I believe both training methods are adequate however.
    I believe either option is better then having neither and the technology once understood works very well in helping make informed decisions on how you treat your diabetes.

  9. Jogger March 10, 2017 at 7:25 pm - Reply

    I would wait or look at another company. It is impossible to get supplies for the Dexcom G5 that I was convinced to purchase. Now, 9 months later I can say the pharmacy Edgepark is useless and has no concern for their clients.They will not or cannot process refill request in a timely manor.

    • alicia downs November 2, 2017 at 12:02 pm - Reply

      Hi Jogger,
      We definitely commiserate on pharmacy difficulties, but would point out that Dexcom and Edgepark are not the same company. Edgepark is a third party distributor. If you are unhappy with their service, reach out to Dexcom and request a new vendor pharmacy to use, or even to purchase directly from Dexcom. It may cost a little more, but better customer service is worth it. Dexcom would also benefit from knowing what suppliers are not properly meeting their clients’ needs.

  10. Blondina Tuitt July 3, 2017 at 7:59 pm - Reply

    If I use an omnipod to check my blood glucose then place my blood glucose in another what is the purpose of two machine on my body I am happy others find it to be beneficial it is very invasive on my I can handle the omnipod that delivers the insulin sticking my self with a needle ain”t gonna happen

  11. David October 30, 2017 at 12:59 am - Reply

    Dexcom needs to allow users to access and review all insulin adm., carb intake, activity, & glucose values together numerical and graph. This needs to be storeable for review, not lost after sensor change. One needs to be able to see the big picture to manage diabetes. A snap shot is nice for a snapshot in time. To prevent the complications one needs to see the big picture. At least to easily review the events that were entered?

    • alicia downs November 2, 2017 at 12:05 pm - Reply

      dexcom data is view-able on the receiver or phone app in a snap shot. however that data is then uploaded (automatically from the clairity app, or manually from the receiver) into the Dexcom Claritiy website. This give full reports with an extensive history. You can reach out to us at Integrated Diabetes Services for training on downloading, accessing and even analysis of your CGM data and how to apply it to your diabetes management.

  12. Linda Lahovin August 9, 2018 at 8:48 pm - Reply

    Had a unit for about 6 months. Do not trust the readings, sometimes indications are 40 points higher or lower.

  13. Kevin October 1, 2018 at 5:35 pm - Reply

    I’ve got the G5, and will be upgrading to the G6 in October 2018. I am very disappointed in Dex’s poor technical service in getting an Android app to run the system on without thinking about a CGM, I sunk $999 in a Galaxy Note9 and the software doesn’t work on it. It does work on a 10 year old iPhune IV relic.

  14. David Thompson October 29, 2018 at 3:46 pm - Reply

    Dexcom has a great product but non-existent customer service. You will wait at least 30 minutes for either order or technical support on the phone. They will stop processing your order because something is needed from your doctor, but NEVER request the needed information from your doctor. As a result, you end up with no product for weeks at a time and have to call in, waiting hours to speak with someone. once their are notified of the issue, the needed data is then requested from your physician. The physicians response will take at least another week before they have it in their system.

    This makes for a complete nightmare and I am looking at alternative CGMs from companies that do not have these issues.


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