Review: Dexcom G4

I haven’t read the recently released Diabetes Australia National Diabetes Strategy and Action Plan word for word yet. However, I was excited to see that as part of their election platform, DA are recommending that “people with diabetes in certain high risk groups should have government supported access to Continuous Glucose Monitoring technology (e.g. hypoglycaemia unawareness)”.

Yes please! If DA can achieve an advocacy outcome on this one, I will be one happy dude with a stuffed pancreas. One of the main things I want with my diabetes is to feel in control. CGM goes a long way making that happen.

This announcement prompted me to finally finish start my review of the Dexcom G4 system that recent hit Australian shores. I was lucky enough to give the Dexcom a trial run through my diabetes clinic a month or two ago.

There are a number of reviews of the Dexcom G4 out there including The Insulin Crowd, Six Until Me, A Consequence of Hypoglycemia, Arden’s Day, The Girl with the Portable Pancreas and others, so I think the basics of the system are well known. I will just try to offer my thoughts on my experience with the system. I’ve probably forgotten stuff over the journey, but I’ll give it a go. Bear in mind these are just my thoughts after one wear of the Dexcom.


Well, I was lucky enough to trial the system through my diabetes clinic. I’m a gadget kind-of-guy, so when I heard the Dexcom had been released, I thought I’d give it a go. I used the Dexcom G4 with the stand-alone receiver, as opposed to integrated with the new Animas Vibe, and based on learnings from other blogs (here, here and here) covered the sensor with enough OpSite to cover a small country. Being a Medtronic pump user, I have used the Medtronic Enlite sensor about 5-6 times now, and I’ve blogged before about how valuable I find CGM technology. Whilst I like the Enlite, I found that I much prefer the Dexcom system.

Despite the Dexcom transmitter being somewhat larger than the Medtronic one, I actually found it to be reasonable comfortable. Bear in mind that this was only my experience of one sensor, but I certainly found the Dexcom sensor more comfortable under the skin than the Medtronic one, especially when sleeping or knocking that area accidentally. There was no tenderness around the area, which I really value. Further, the Dexcom sensor left no visible signs of “damage” on my skin after wearing it.

So What?

I got a whopping 17 days of life out of the sensor with no need to reset the sensor. 17 days! It was still reading equally as accurate on Day 17, and continous patch up work with the OpSite helped it to hold on really well. Was only near the last day or so it was starting to weaken.

By comparison to my experiences with the Enlite…well, that is pretty incomparable Dexcom are pretty clear in their documentation on recommending you use the sensor for ~7 days, but there are significant examples of people out there getting great results well over 10-15 days. I only took the sensor out because I was going away, and also because the sensor was only JUST hanging on for dear life. I was keen to give it a few more days, but conceded defeat.

What about carrying another device, you say? Sure, I already carry my pump, meter, strips, pricker, spare insulin pen, jelly babies, etc, etc, etc, but to be 100% honest, I like the fact the Dexcom G4 has a stand-alone receiver. I carry my pump in my pocket about 98% of the time, but I quite like looking at the CGM graphs on a regular basis (read, every 32 seconds). Therefore, I actually find it tedious pulling the pump out so many times per day to check the CGM data – not from an embarrassment point of view at all, but just one of those really minor things that becomes annoying after the 325th time.

I would place the Dexcom near my work computer and would look at it during the day. The benefit of the long range, means I could leave the Dexcom on my computer, go to the kitchen or printer and come back and it hadn’t lost transmission. I also placed it in my car console area when I was driving to work or on work trips. Above 5 to drive and all that.

Now What?

If finances allowed, I would quite easily use the Dexcom system for about 330 days of the year (I say only 330, because sometimes you do need time apart from gadgetry!). Alas, the costs are absolutely prohibitive. or in my car console area when I was driving to work or on work trips. At $810 for the receiver, $595 for the transmitter (that needs regular replacing, see below) and ~$400 for 5 sensors…I mean…that’s a lot of coffees. I place enormous value on my health and already pay a fair bit of cashola on my diabetes. I love the Dexcom, but can I justify that cost when I still need to be able to do things like…eat?

Given this, I’m stoked to see that Diabetes Australia has placed the issues of CGM affordability and accessibility in their Election Platform. Access to things that will improve my quality of life and diabetes management are important to me, and I appreciate the diabetes peak organisation equally valuing this.
The good

  • The receiver looks modern and feels good in the hand, with a massive screen to ensure that the graphs don’t appear squashed. And colour graphs. My kingdom for colour graphs. They made it really easy easy to look at quickly. Above target? Yellow. Below target? Red. Simple!
  • Trend arrows – in my opinion, they were much more reliable than Medtronic, and offered greater information. I changed the factory settings set at 12.0 mm/ol to have my high alerts above 10.0 mm/ol. Better to catch those nasty highs early.
  • Relatively comfortable insertion and wear (obviously depends on the spot you hit, though). The transmitter looks pretty large, but I found it barely noticable.
  • With the Dexcom on a table next to the bed, the alarms DEFINITELY woke me up (I know some people keep it in a glass for extra noise and reverberation. I have found in the past that the Medtronic CGM didn’t wake me up because it was in a belt thing around my waist and hence under the covers.
  • The vibrate function is equally good, especially when I was in meetings for work. It was certainly easy to pick up on the vibration alerts.
  • It was accurate. Many other bloggers have found it to be more accurate after the first 24 hours, and I certainly agree with that to be the case. Was usually within 1.0 mm/ol.20130628-182300.jpg

The bad

  • Cost. Ca-ching!
  • The transmitter is not rechargeable. After forking out cash for the receiver, sensors and the transmitter, they ask you to buy ANOTHER transmitter down the track? WTF. It is estimated that they last 6 months or so, and then need replacing, costing a tidy sum. I find this extraordinary given the Medtronic Enlite transmitter is rechargeable
  • Is it just me, or is the button temperamental? Sometimes I pressed it. Got nothing. Pressed again, and the screen wakes up. I think it is a bit like pressing a TV remote button where you just don’t quite press it in the right spot, so it ignores you or when your iPhone gets really old and grumpy, and the button gets less responsive. If you check your Dexcom regularly, it can be frustrating but manageable.
  • The case that comes with the Dexcom is…bad, but I know you can buy other ones online.
  • Whilst I raved about the alarms earlier, they can be annoying and even the quiet setting is VERY loud!
  • The receiver probably needed to be charged every 4 days, which is probably not too bad, but felt slightly frequent. Minor complaint, though.


So that’s that. CGM rocks in general, but the Dexcom rocks twice as much. I still prefer the Medtronic pump but prefer the Dexcom CGM, so I have a foot in both diabetes product camps.

Best wishes to Diabetes Australia in fighting the good fight for accessibility of CGM systems to all Australians living with type 1 diabetes. Hopefully within the next couple of years, we will have CGM systems subsidised here so more people living with diabetes can reap the benefits from the technology.

Happy to answer any questions!

Disclaimer: My test drive with the Dexcom came through my diabetes clinic and not AMSL, distributors Dexcom CGM in Australia. However AMSL did supply me with a sensor to use for this purpose. I have absolutely no arrangement with AMSL to write about my experiences with the Dexcom, I just really like the system.

6 thoughts on “Review: Dexcom G4

  1. I have been using an Animas Vibe pump since early this year and would, like most people, LOVE to try the Dexcom CGMS along with it to see how much benefit I could get from one. My only concern with doing that is I’ll have to give it back and be left wanting one even more. As you said the ongoing cost is just prohibitive as it is now but as soon as they make it to the NDSS I’ll be signing on the dotted line.

  2. Pingback: Dexcom – trial two. | Insulin pumps need Tetris

    • Hi Karl. I believe it’s just the standard Dexcom cover. It’s okay but pretty bulky and not great if you wanted to carry it in your pocket. I understand there are slimmer options out there.

      Hope that helps!

  3. how often do you change the sensor?? the price of a box of 4 is quite expensive here in Australia and is the only drawback to me at the moment, but if you tell me that I can keep it for more or at least for 2 weeks, I’ll definitely go for it =)


    • Hi Matias, I have only used it for short periods of time because the cost is a barrier for me as well. If the cost was cheaper, I would use it pretty much 24/7. With that said, the times I have used it, I have definitely got some pretty extensive use of out of it. Hope that helps.


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s