G5 Sensor Life

I used to be able to get 2, sometimes 3 weeks out of my G4 sensor. Now with the G5, I get ? or signal failures after about 9 days and I have to insert a new sensor. Anyone else experiencing this? Seems odd since the sensors are still the same…

Hey MissAng - I’m on day 22 of my second sensor (first sensor I just popped of G4 and put on G5 when I received it and it last me 26 days combined). Are you using a different site maybe?

I always use my thighs but maybe I’ll have to try somewhere new. I can’t think of anything I’ve done differently. Do you ever take your transmitter out and wipe it down? I usually don’t. Last night it said there was a problem with the software and I had to delete it from my phone and reinstall.

i always take my transmitter out and wipe it down with an alcohol swab. i alcohol swab everywhere i can. i also wash my hands before doing any changes. one thing i have noticed with the G5 is that it is much more sensitive than the G4. whenever i calibrate it, i lose the direction arrow for a bit, and i also notice that i can get an “out of range” icon much easier than i did before, however,i have never gone more than 10 days with one sensor. i just end up getting the ??? and then i take it off and put on a new one. i am so jealous of all of you who manage to wear it for such long periods of time. i hate putting in a new sensor, finding that sweet spot, no pain from new insertion site, ext.

good luck

Only time I wipe my transmitter with alcohol is when I change my sensor.

I had been experiencing early sensor failure, after about 10 days, a while back. I started drinking more water and found my sensor life increased. It could be coincidence but it makes sense to me that sense the sensor needs interstitial fluid to measure BG, perhaps being dehydrated adversely affects sensor life. I’m still not getting the dependable 14-day sensor life but it has improved. I’m on day 11 of my current sensor and it’s going strong.

By the way, I learned in my electronic technician work life that isopropyl alcohol leaves a film of residue when it dries. A clean rubber eraser works better.

i was having problems with a new sensor this afternoon. i called dex tech support. the rep suggested that i drink some water, that i might just be dehydrated, also b/c i am so lean, there is not as much necessary fluid for the sensor to read. so i drank the water, and the sensor came back to life w/in about half an hour. maybe just a coincidence, but i like to think that water is a good go-to solution for an obstinate sensor.

i love my arms as my site for the dexcom. In 9 months I have never used a different location. I also wipe the contacts (back side) down with an alcohol pad before use.


I’m starting day 11 of my very first sensor, @MissAng! For a few minutes yesterday, after I boarded the airplane, I got. a lot of ??? and thought to myself “uh oh”. But I just happened to drink some more water and got data back about 15 minutes later. :grinning:

As a side note, I had no problems going through security and using a CGM while traveling is truly a blessing!

Glad to see this discussion. I’m up for replacement of my G4 transmitter and some more sensors, so I’m asking my Doc to update my prescription to allow the G5 upgrade (required by insurance…) I do hope to get similar results out of the G5 that I did on the G4. I’ve also seen on the G4 where not only water affected the life of the sensor, and it’s accuracy, but my whole diet and even vitamins could have small noticeable effects.

My daughter just broke her personal best record and used a sensor for just shy of 4 weeks. That sucker was still accurate, too, but we changed it because she said it was starting to feel uncomfortable. Sure enough, there was a sizable red hole oozing some interesting-looking pus. Won’t blame Dexcom or anyone but ourselves, but we certainly got our money’s worth out of that particular sensor. And it definitely helped out with the stockpile I’m accumulating for the Zombie Apocalypse (it’s just a matter of time, trust me…)

When I first learned about longer life on the sensors, I tried for as long as I could stand. Got just over 9 weeks, but then got the “it doesn’t feel good” situation too. Upon removal there was a very red patch around where it was. I’ll never go that long again. Just too dangerous. But I can get between 2 to 4 weeks almost all the time now. Usually remove it when the dressing I use, which is a lot of 3M Tegaderm tape, starts to become a problem and is not protecting the site as well as it should. I use lots to keep the site as clean as possible for the longest time. Sometimes I replace some of it to extend a few days, to make it easier to schedule a change. Or I’ll remove it if I get even the slightest indication that it doesn’t feel right, as I don’t want to have to mess with infections again.

So far I’m averaging about 12 days. The adhesive on the previous came loose and I didn’t notice before I showered so I decided to change it but It was still performing accurately. I have ordered some OpSite FlexiFit over the Internet but don’t have it yet.

Edited 12/26 to add: My last sensor lasted 3 weeks!!

For me after about 2 weeks the sensor starts reading lower and lower compared to my meter for some reason. Even when I try to correct it it just isn’t as accurate so I pretty much stick to a couple weeks. I did get an infection once also like @rgcainmd 's daughter on a tummy placement (which I no longer use) so I’m hesitant to go much beyond the 2 week mark.

I know that this is hard to believe but I restarted my sensor after the first week on October 31. It is still going strong. I am sure this won’t be the case with my next sensor. I was never able to get more than 12 days before. I have to pay out of pocket for my sensors so I am happy with any extra days I do get out of them.

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My sensor site isn’t bothering me. Should I end this session anyway? Nov 31 will be 4 weeks. I don’t know if this makes any difference but, my sensor is in my arm.

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If you have never gone 4 weeks previous, I would consider it a good idea to stop the session, remove the sensor and inspect the area under the sensor patch. Make sure it looks good.

Next time if you want to push it longer and go 5 weeks then see how it is.

IMHO better to be cautious and make sure no skin irritation or other issues waiting for you under the patch as opposed to pushing it too far.

At the end of the day obviously it comes down to your level of comfort in how you approach things.

I usually get about 3-4 weeks out of (G5) sensors, however my most one lasted 6 weeks. It was stunning and it was still bang-on accurate (within 0.1-0.2 mmol/L (2-4 mg/dl) when calibrating often.

I still do 5-7 finger pricks per day

Yeah, I got a little worried from reading some of the posts so I ended this session and to my surprise there was nothing on my skin to indicate that it has even been in my arm. I will let it go next time until it dies I think.

Myself I would still be cautious and extend a week further at a time.