Ordered my first CGM

Well I finally took the plunge and decided to order myself a Dexcom G5 glucose monitor. Due to the current state of the Australian Health Insurance industry I’m funding it completely out of pocket, so I’m not sure if I will be able to continue to use it after the inital transmitter runs out.

I figure if I find that it helps me out enough in the next three months that I can find a way to fund it somehow.

I’ve read quite a few informative posts on here, but does anyone have any general advice on how to best utilise the device? Despite reading positive experiences of placements on the thigh or arm I think my first sensor will go stomach, and then maybe I will try my thigh to see if it’s better.

I’m quite excited to start using it and hoping it arrives this week :smiley:

I’m in Canada and am also self-funding the Dexcom (though we only have the G4 here). Since wasting a sensor is wasting $85, I didn’t venture out past my stomach until I’d been using the system for over a year. I have my second arm site ever in right now, and I hope it lasts as long as the first one did (lasted 46 days). By stretching sensors out as long as possible and using the transmitter and receiver until their batteries are dead (which, for the G4 at least, last well past the six month warranty, though the G5 I’ve heard is programmed to die once the warranty period is up) it’s possible to greatly reduce the costs, though the system is still extremely expensive. When I began using it my intention was to use it intermittently, but the CGM helped me get and keep my A1c at 6.0-6.2 for the first time in my life, and so I’ve used it continuously since getting it.

Good luck with it! I hope it’s as helpful and life-changing for you as it’s been for so many others.


Congratulations! You will love the Dexcom. I’ve been using it for nearly 7 years now, currently with the G5.

As for any tips, when you first start…don’t get to absorbed with the information. I know I took it very personally in the beginning. Just remember, it’s providing information to help guide, and make adjustments. I remember in the beginning I would get too aggressive with corrections because I would see the straight up arrow, and a pending high…only to come crashing back down etc.

Less calibrations are better, I only calibrate the twice a day required…unless a reading is wayyyy off (which is very rare). Best to do the calibration when you are ‘flat’, and I try to do it at least 10 minutes before I plan on eating anything. Just to give it two readings of a stable number.

Besides that, it’s a great tool…and remember it is exactly that. A tool to help you. Good luck! :slight_smile:


You should get a copy of Gary Scheiner’s Practical CGM: A Guide to Improving Outcomes Through Continous Glucose Monitoring – excellent book on how to get the best value from the CGM.

Also, I’m sure you have read on the forum that many people leave sensors on more than the one week labeled, assisted by extra tape such as Tagadern or Opsite Flexfix, or many other options. That can help stretch at least that part of the budget a bit.

Good luck with it!



My best advice:

-Be patient at first and don’t expect numbers to match exactly to finger sticks.
-Only calibrate during periods of low glucose fluctuation (i.e. not after meals, exercise)
-You are NOT required to calibrate immediately when you get the notification to do so. Often I get the calibration pop up when I just ate and I wait to calibrate once I know my BS is relatively stable.
-Don’t over calibrate. Only calibrate when prompted or when there is a significant difference. I’ve posted the guidance from Dexcom’s site numerous times here so take a look for that.
-You can use sensors for many days over 7 but your YDMV here. I consistently get over 20 days with my sensors.

These are only a few things, but a good start.

Good luck!!!

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You’re probably aware of the 15-minute lag-time between a fingerstick number and a CGM number. When your CGM is well-calibrated and tracking your BG well, it may cause you to forget about that lag-time.

When I first started using a CGM I would tend to over treat lows by watching my CGM trace as an indicator when to stop treating. Due to the 15-minute lag, when my CGM read 55 mg/dL as I was treating my low, a fingerstick might reveal an 85 mg/dl, a number that indicates the hypo treatment is working and I no longer needed to continue eating.

Our counter-regulatory hormones already entice us to over-treat lows; don’t use your CGM number during a low as it may cause you to over-treat. The same can be said when going high and adding insulin. This is also a case when a fingerstick confirmation would give you more timely numbers to use.

Are you only getting one G5 transmitter in your kit? In the US, the initial kit ships with two transmitters. Two G5 transmitters should be priced at about the cost of one G4 transmitter. I fear that middle-men may be taking advantage of this.

Good luck. I’ve been using a CGM continuously since 2009. It improves my life.


Thanks everyone for some great posts.

I didn’t realise Gary Scheiner has a book specifically for CGM use. I actually recently obtaineda copy of his Think like a Pancrease book, which I’ve found informative. Admittedly it is a lot of reinforcing stuff I already knew/do but he raises some new concepts I’d never heard of before.

@Terry4 There is only on distributer for Dexcom in Australia, when you order it you can get extra transmitters with it but as standard it comes with 1 Transmitter, 1 Receiver, and 4 sensors. At the moment they actually give you 4 sensors for the price of one. I didn’t want to invest in a second transmitter until I had tried it out for a bit. The G5 transmitter in Australia is only $40 cheaper than the G4 transmitter, the G4 i beleive is $580 per transmitter, with the G5 being $540 so unfortunately we don’t seem to have the same luxury of half price transmitters.

I’m aware of the 15 minute lag, in fact it was a point that my endocrinologist used last year to turn me off using CGM. My understanding though is that you calibrate the meter so that even though it technically lags by 15 minutes, it reflects what your blood glucose reading shows in your standard glucometer. Is that correct? If not, how do people constantly find they have fairly similar readings with their standard glucometer?

One point I’m really unclear on is the ‘accuracy’ of the G5. When I met with the Dexcom rep for my region she told me that the G5 has a 9% area of difference to your plasma blood glucose readings. This would to me indicate that it’s potentially more accurate than your standard glucometer, which have a 15-20 % discrepancy.

During times of stable BGs, the 15-min old BG is the same as the current fingerstick BG. It’s during the times if more rapid change that the CGM number can fool you into taking inappropriate action.

If you’re getting 4 sensors for the price of one, then that’s where you’re getting a break.

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Wow, if I had a choice of these I would definitely be going for the G4 as someone who is entirely self-funding the system. Their accuracy is the same, the only difference between them is that hte G5 can be displayed on an iOS device. Do you have a pressing need to have your readings displayed on your phone? If not, going for the G4 would seem a much better choice financially (if that’s an issue).

I find that my Dexcom often matches my meter when my blood sugar is stable, because the current reading is virtually the same as 15 minutes in the past. But when my blood sugar is changing rapidly (slanted, straight, or double up or down arrow on the CGM) my readings can be much higher or lower than the CGM reports, and then the CGM will gradually catch up over the next 15 or so minutes. Because of this, I move my low alert up to 4.5 mmol/L or even 5.0 mmol/L if I’m nervous about going low.


I do have a preference to have it on my iPhone for a number of reasons. I am looking at getting an Animas pump in the near future as well, so if I decide the G5 is too expensive to fund I will move to the G4.

It was my understanding that the G5 is actually more accurate, due to the algorythm the transmitter uses, than the G4. I’m sure some people dispute this though.

Admittedly, I had for some time thought the G5 was too expensive for me to fund. To some extent it is, but I just really had this urge to explore my options and see how it went in terms of improving my control. If after three months it’s not really made much of a difference then I may ‘throw the towel in’.

The G4’s break down as pre- and post-505 software upgrade. The 505 firmware flash made the G4 more accurate. The G4 share with the 505 update is equivalent in accuracy to the G5.

I’m using the G4 now after three months with the G5. I mostly use the receiver and Apple Watch to monitor BGs.

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Interesting, I guess the problem I have if I find the G5 is too expensive for me to keep is that I will need to get a G4 receiver, which for me in Australia is about $800, almost equivalent to two more G5 transmitters. So one starts to ask if this would actually save me money.

I’m still hopeful that either Dexcom will drop their prices in Australia in the coming year, particularly with the advent of the Medtronic 670G or Health funds in australia will start offering some level of cover for CGM devices. Even a few hundred a year would be nice.

If you’re getting a Vibe, though, that would negate the need for a G4 receiver. Whichever system you go with, I’m sure you’ll find it helpful!

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As far as I’m aware the vibe doesn’t use the most recent firmware, so it is not as accurate as the G5 but certainly if I’m pressed for finances that could be an option! I guess I’ll have three months to see what I think of the G5.

As far as I’m aware, I’m using the older software on the G4, since I don’t believe we have the update in Canada (everything takes forever to get here). I find my Dexcom pretty accurate. Maybe I’d find the new software even more accurate, but for trending and early warning of highs and lows, I haven’t had any problems with mine and can’t imagine any way it could be even better (except if sensors lasted 30+ days and there was no 15-minute lag and the system were affordable).

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2 words: SKIN TAC. You can thank me later.

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Out of curiosity Jen, how much does one transmitter cost you in Canada?

We don’t have the G5 here, but one G4 transmitter costs $800 CAD.

How exciting - good luck!

I echo the recommendations on calibration - don’t overdo it and you don’t have to do it as soon as it asks for one. Caleb is notorious for under calibrating and it doesn’t appear to affect accuracy.

I would recommend using the Dexcom Clarity software. It has some very useful presentations of data which I find very helpful in making dosing adjustments.

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Wow, why does it take so long for new tech to get to canada? I thought Australia was bad.