Dexcom G4 sensors are driving me crazy! Help!

Could you list at least some of the skin barrier site preps you’ve tried? If you don’t tell us what you’ve tried then we are likely to just suggest it again.

Just a complete gut level guess here, but the site prep you describe strikes me as more likely to lead to irritation than to prevent it. It sounds like you are essentially removing any “natural barrier” your skin might have. :confused:

Do you run into the same problem no matter which location you insert the sensor at? I find that how my skin reacts seems to depend a lot on which area of skin I use.

Ironically, I seem to be most sensitive on my abdomen. I had a really bad skin reaction when I inserted my Medtronic sensor on the left side of my abdomen. I also have had poor, though not quite as bad, luck elsewhere on my abdomen. But never really much of a problem using my thighs.

With the Dexcom you also might be able to use a spot on your upper arms. At least other people have posted about successfully inserting their Dexcom there.

Not that uncommon. Two suggestions:

  • Give tegaderm a try and see if you can tolerate it on your skin for days. Most people with allergic skin reactions to typical medical adhesive pads tolerate tegaderm well. Its the same stuff as on those Nexcare waterproof bandaids, except just in solid sheets of the stretchy, elastic rubbery film. If you can tolerate tegaderm, then just apply a 2x3" patch of the film on your skin, and put the sensor over the top of that – adhesive pad and all – and punch right through the Tegaderm film when inserting the wire.
  • Removal: I swear by Unisolve. I should be hired as a spokesperson. I got these same angry red “rashes” from both G4 sensors and (usually worse) removing finished Omnipod pods. It’s the result of the top layers of your skin being ripped off, down to an immature layer below. The best way to prevent this is not to rip that skin off. Use a good adhesive dissolver, like Unisolve, to first soak the pad, wait a few minutes, then gently remove the sensor/infusion set/pod. It practically slides off. Then, clean up with a gauze pad, wash closh, cotton ball – doesn’t matter – soaked with a bit more Unisolve, and wipe clean with a soft washcloth. Your skin will be like the sensor was never there, except for the tiny puncture.

I use IV3000 2 3/8in X 2 3/4in transparent dressing under my sensor(Tegaderm is basically the same thing). It fits almost perfectly under the Dexcom adhesive.
I make sure to cut a rectangle in the middle of the dressing where the actual sensor will insert into my skin so that nothing will get on the sensor itself.
I also use IV Prep on my skin before putting it down, making sure to leave a little rectangle dry in the middle again where the sensor actually penetrates the skin.
I have extremely sensitive skin and the Dexcom adhesive is definitely more irritating than my pump infusion sets. I don’t have to put anything under them.
Also, I don’t put any lotions/creams where I am going to insert, that is just asking for trouble.

Yeah, I’ve noticed the same thing but I’m not sure whether the difference is the adhesive or simply that I wear the sensor for a much longer time than an infusion set.

(Note: And I usually only wear my CGM sensor for at most 6 day because I use the Medtronic Enlite CGM sensor. Not sure what it would be like wearing a Dexcom for as long as folks report that they do. :confused: )

How come you are only wearing it for 6 days? I’m on day 10-1/2 at the moment and the sensor is going strong. great ISIG, so good response to changing bg’s and accuracy is awesome. My wife just finished a 12 day stint with her Enlite yesterday. I go 12 days on nearly every sensor that works well for the first 3+ days. If it doesn’t work well by day 2-1/2 I call MM and get a replacement if it’s clearly bad (ISIGS refuse to get out of the single digits)

Two reasons.

First, I currently don’t get consistent performance from my Enlites which you are experiencing. I’m glad when I do make it to day six. I’m on day six for the current sensor and the ISIG was around 15 for a 100 SG. When I started the ISIG was more like 25 to 29.

The sensitivity (?) of the probe seems to degrade somewhat steadily over time for me. I’m not quite sure if this is a problem with the probe’s chemistry or, I think more likely, because my sensor probes get “kinked up” the longer I wear them.

I decided to break this out and post it as a separate topic. My intention was to spin it off as a “linked reply”. But for reasons which escape me, the linkage didn’t get set up correctly. So, I added my own kludgy link to my new thread: Slow, progressive Enlite ISIG degradation as the days pass :confounded:

Second, I was mistakenly sent 6 boxes of 5 Enlites each instead of the single box I was ostensibly prescribed. While I do not have to pay out of pocket for this, it still infuriates me because it is stupid beyond any words I have and a general PITA.

On the one hand, I’m don’t have to worry about resupplying during the next 6 days * 6 boxes * 5 per box ~= 180 days after I received them.

On the other hand, Enlites never have an expiration date longer than 6 months from their date of manufacturer. My 26 remaining unused Enlites all “expire” 90 days from now on August 13 and at 6 days each I’ll have only used ~15 of them by then. The last ~11 Enlites will have technically expired before I can use them. If any of them completely wonk out on me, I won’t have the option of asking Medtronic to replace it.

Bottom line is that I am not “incentivized” to try to use them for longer than the 6 days Medtronic specifies. :angry:

Oh, well … at least I’ve got CGM. :partly_sunny: No point obsessing any more than I already do about the details. :blush:

1 Like

Are you talking about the Unisolve pads or the bottle of liquid? It sounds just what I need. I have been using Skin Tac to stick down the Dexcom sensor, The current one is showing no signs of peeling after 7 days, but when I removed the last one I peeled off a layer of skin, healed quickly but I want to avoid a repeat. I’ve never had problems sticking or removing infusion sets but they only stay on for 3 or 4 days.

I make sure to cut a rectangle in the middle of the dressing where the actual sensor will insert into my skin so that nothing will get on the sensor itself.

This obviously doesn’t hurt, but it isn’t necessary (and it does expose some skin to the G4 sensor pad adhesive.

The insertion mechanism consists of a hollow needle with the sensor wire inside. When you push the inserter needle into your skin, the wire rides in with it, completely enclosed and protected from contact with anything. Then, when you retract the needle, the wire stays in place and the needle slides back off of it, exposing the wire with the all-important enzymes to the interstitial fluid environment.

Further, if you examine a sensor wire closely after removal, you’ll notice there is a small margin at the tip where there is no coating – that part of the wire doesn’t participate in the sensing.

Finally, I use SkinTac before applying the G4 otherwise it won’t stay on for the two weeks I get good accuracy out of them. Been doing this for two years. Never had the SkinTac cause any problems punching through it with the inserter.

Both, actually, but the individually packaged pads are just a convenience.

I wear my sensor and pod on my upper arms, and when that locale gets too abused I wear the pod on my thighs for a month or two until the arms are healed enough be be abused again.

And yes, I just give the entire adhesive pad a good soaking, wipe the excess off my arm, and do something else for a few minutes (I’m usually filling a new pod, so it works out very conveniently). After 3-5 minutes, the dang thing just “slimes” off.

Unisolve smells awful – you’ll think you just creosoted your body or something (not nearly that bad, but you get the point). In my experience, though, it’s wonderfully gentle on skin. The main ingredient that breaks down the adhesive is some form of parafin, which leaves skin nice and moisturized.

I use the pads for “on the go” mostly. I had all kinds of skin problems, irritation, rash, itching, etc. etc. etc. early on when I was ripping this stuff off, as gently as I could, but still glued to me. It all went away when I started using unisolve and leaving my precious top layers of skin behind where they belong :wink:

30 Enlites for free? you lead a charmed life, my friend. :slight_smile: I pay about $20 for each one and as soon as I lose private insurance I will have to either pay full bore or do without.

for me, worse than Unisolve is Mastisol. despite having paid $22 for a tiny bottle of it, I stopped using it due mostly to the obnoxious smell, and dubious efficacy of the product in comparison to Skin Prep.

I wonder if that is also true for Medtronic’s Enlites. I know that it was not the case previously. The introducer needle of the Sof-sensor (aka Harpoon) exposed some of the probe. But I have no idea what the layout is with the Enlite.

My main reason for continuing to listen (somewhat) to Medtronic’s recommendations and avoid applying Skin Tac or Mastisol or whatever prior to inserting is my concern that the residue could contaminate the sensor probe during insertion and “gunk it up”.

Of course, if I were to ever risk breaking a sensor by not following the rules while inserting it, I suppose this would be that time. Maybe 6 days from now I’ll try talking a walk on the wild side … in CGM terms. :wink:

How about alternative sites? Have you tried your arms? I’m reluctant but intrigued to do so–my wife has had great results on her first and only one. first 10 days were excellent and 11 and 12th days ok except early in AM. she just started her second arm site today so no data yet.

I paint my Dexcom adhesive with Skin Tac and let it dry before attaching. I think it works as a barrier because I don’t get rashes that way. Here is a recent blog post I read recently addressing adhesives and severe allergies:

Also check out Kerri Sparling’s blog about Dexcom and rashes. Here are some of her posts that talk about what she does. Toughpads seems to be a big help.

Dave is on point with the UniSolve recommendation. I use SkinTac and Unisolve for both my infusion sets and my Dex sites and it makes removal near painless.
Just remember to soak the pad portion of your infusion set or Dex and LET IT SIT for at least a few minutes.
Again, Dave is completely on point. If you don’t let it soak in and then wait a few minutes, you will still take skin off.
So just be a little patient and from now on you should have no more damaged skin from removing your sets. :smile:

As for the nasty itching, after switching to using the SkinTac I no longer get the horrible rashes and hives that I used to, but the sites will still itch after a few days as you mentioned.
The amount of itching though, I have found is completely dependent on where you place your sensor.
I know a couple others mentioned it already but using the back of my arm is pretty much the only site where I don’t get any itching whatsoever.
Please do check back in and let us know how it goes.

Just remember to soak the pad portion of your infusion set or Dex and LET IT SIT for at least a few minutes.
Again, Dave is completely on point. If you don’t let it soak in and then wait a few minutes, you will still take skin off.

That’s assuming you live in the USA and can get Skin Tac in liquid form. Apparently the US authorities deem that Skin Tac liquid is SO DANGEROUS that it cannot be sent by air mail. Over in the UK the only way we can get the stuff is in the pad form.


1 Like

Do you mean ineffective at dissolving Skin Prep? IIRC SP is an adhesive like Skintac, isn’t it?

That said, Unisolve is very effective on the adhesive used on the Dexcom G4 sensor pad, the Omnipod pump pad, and Skintac. That’s my universe of medical adhesives and solvents, and it’s a combo that works well.

As for the smell of Unisolve, it really isn’t that horrible, and after wiping away the excess after removing the device, the smell is pretty much gone.

Regardless, I’d put up with an odor much, much worse for the exceptional results, and the protection my skin gets as a result.

Go for it! I’ve been punching through Skintac for nearly 2 years now, and have never, ever, had any problem. I became quite confident of this after thoroughly disassembling an inserter, “rearming” it (of course, without the wire in it), and reverse-engineering how it worked. It’s a very clever mechanism.

Simplifed, there’s a hollow needle with an angle-cut sharp tip inside a slightly larger, shorter, fixed metal tube.

When you push the plunger in, the inner needle containing the wire is pushed through the larger tube, which acts as a stabilizing guide, and penetrates to the correct depth. The last mm of the wire is not coated and is not active in sensing BG, so any tiny amount of contamination resulting from the insertion process (remember, skin and other cells “gum up” the opening of the needle as well) is of no concern.

At the very end of the plunger’s travel, the mechanism of the inserter locks the outer guide tube in place, which also clamps the wire so it can’t be pulled back out. Then, when the outer ring fixture is pulled back with your fingers, the insertion needle is withdrawn from the site of penetration, the wire breaks in the body of the little contact flap on the sensor body, and voila!

The rule of thumb for CGM sensors is any skin that has a lot of perfusion – high blood flow, consistently and reliably.

Ironically, fat tissue is not one of the best tissues in this regard, however it’s all we have to work with (subcutaneous fat). If we could get that sensor into, say, interstitial cellular fluid in the kidneys, we might have a 1-2 minute lag in the data rather than 5-15.

“5-15?!?!???!?? Where’d you come up with 5 minutes, Dave, and can I have some of what you’re smoking?”

Second question first: No, you can’t.

As for the 5 minutes, I can only report what I’ve seen. If I wear a sensor on the side of my thigh where there’s a fairly thin layer of fat, and then get up and get on with my day, I’ve seen G4 data being as little as 5 minutes delayed, estimated of course.

Problem is, it’s extremely hard to slip that sensor wire in just right in the middle of the subQ fat there. 3 out of 4 times it’s either too shallow, so I get worthless readings, or it’s just a tad too steep, and keeps poking/scratching the surface of the quadraceps. The latter starts out as a minor irritation, but after several days it gets sore and unmanagable.

So, it’s arms for me, and no where else. I have usually about a 10 minute delay at that site. I get the advertised 15 or so when I use Dexcom approved site, my belly.

I discovered with the pads is there is a fair amount of Unisolve liquid left in the foil packet when you remove the pad.

So, after using the pad/towelette to transfer as much Unisolve as possible to the target adhesive pad, I carefully take the packet, put the open end on the target, then invert it and squeeze the excess liquid out. I usually get a meaningfully significant amount of extra liquid soaked in this way.