What's the longest a single sensor has been used?

I've used the Dexcom CGM for about 7 years now and learned early on that you could simply restart the same sensor after it expired to get more than 7 days use out of it. Until today, my personal longest time for a sensor had been 20 days. This morning, my current sensor gave me its "I don't believe the blood sugar reading you just entered, give me another one" when the CGM's reading was off by almost 100 points (CGM said 94, but I was close to 200). I began using that sensor 26 days ago - a new personal longest for me! I have no explanation as to why this sensor lasted so long. I was wondering what's the longest anyone has ever gotten out of a single sensor.

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28 days is my longest. Current one is 23 days old today and still going strong.

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I’ve gotten around 20 days or so, maybe a full three weeks. I noted in another thread here some time ago that a Dexcom rep told me they had a fellow in Santa Barbara go as long as possible, and he ended up in excess of 80 days.


I had been doing 14 days just as a routine, changing it on every other Sunday.
But I just realized my sensors expired June 19th & I am down to only one unused sensor left, so am now on day 15 and planning on keeping this one on til I get a new supply or it is no longer accurate. That way I have a spare (albeit an expired one) for an “emergency”.
It is ironic that I am so dependent on Dexcom’s use now, since I fought going on one and at first felt it was my endo ‘watching me like Big Brother’! Now I hate that 2 hour startup time and hope to get a 2nd receiver sometime so I can overlap my sensors as many do!

Once I got around 60 days off one sensor. I wouldn't recommend that, but it did work. Changed it due to what seemed to be an infection starting at the insert point. The sensor was still going good otherwise. Today I get around 28 days. During that time, I do see an occasional 100 point off issue, but not on every sensor. In a few hours and a couple more retests it came back into an acceptable range. I usually see some anomaly during the final week or two. I don't give up until I get repeated ??? displays for more than a couple hours.

I was trying to find excuses to not start too. Now I wish I'd done this years before. I just didn't want to be tied to a device. Now I do both this and an Omnipod. Can't imagine being without either now.

I'm a new user so I'm only on my second sensor. The first one went 35 days, was working great, but I got nervous and pulled it out(stupid newbie!). My second one is currently on day 34 and hasn't had any problems yet. I'm not sure if its beginner's luck or what but since I'm self funding, I couldn't be happier. I use opsite flexifix, dry it with a hairdryer after showering, and massage it if the readings are a bit off, all suggestions I've seen on this site. I've read about the ???? display, but haven't seen one yet.

I don't think I've gotten one to last more than 16 days. Some of that is because the adhesive fails, even when I put some IV-3000 or similar on it.

When I called Dexcom this morning I found out that my prescription is expired, and so has my insurance authorization. So it will probably be at least 2 weeks before I can get more sensors. So now, I will DEFINITELY nurture the one I have on for as long as I can before inserting my very last (expired x1 month) sensor. I am only on day 15 so I should be able to make it.
I was asked if I wanted automatic shipments every 3 months (hell no, that's how I ended up with expired sensors). But now I am wondering what the expiration dates will be on the 3 boxes I DID order. Anyone know how far out the expiration dates go? I am sure it is not too late to change my order to less than 3 boxes. Thanks in advance to my online "experts". :-)

About 21 day (3 Weeks) is the longest I have worn one. Even then I had to put band-aids on the sides to hold it on. I was traveling and couldn't change it. I use Skin Tac and that does pretty good but after a couple weeks the sensor gets loose usually right after I shower in the morning. I wish the 2 hour startup was shorter though.

I just received a box of 3 sensors last month and they had an expiration date of 5/9/2015.

I have been on the Dexcom for two weeks and was intending to re-start the sensor without changing it, however the Tagaderm started giving me a rash. I've sent away for a different adhesive so I hope that helps!

I'm on my 18th day. Longest for me.

My average is 2.5 weeks. My longest is 3.5 weeks.

Removed my ‘oldest’ sensor this am on the 26th day. It was just beginning to stray more than I could put up with.

I went 9 days with my first one but only because the tagaderm gave me a rash. Right now no skin issues with the second one and I’m switching to a different adhesive so I have my fingers crossed.

I have found that the sensor stays in better (helps extend use) by using fabric medical tape (bandage tape). I use two long strips to form a "t or x" over the transmitter. I have the 4 tape ends extend over the pitiful adhesive patch (attached to the sensor) by about 1 - 1.5 inches. My doc says he uses liquid adhesive, but my 'tape it' method seems to work well. BTW, applying the tape like the Dexcom manual suggests has not worked at all well for me....tape and sensor comes off too easily.

I average 21 days. I think the longest use was 28 days. Before I place the Dexcom, I use Bard® Protective Barrier Film Wipes over the entire area. After insertion of the sensor and placement of the transmitter I use a Tegaderm® 4" x 4 3/4" patch directly over everything. This works like a charm and with no more ??? after showering or swimming.

So, what degree of error is everyone getting on these long 14+ days of wearing the sensor? I can't seem to get beyond 14 days without it being way off, more than 50 pts at times. If accuracy goes down, what is the advantage of keeping it on for 20 and 30 days?

I understand that these sensors are expensive, but I would rather have no information and rely on my bg meter rather than incorrect information from wearing a sensor 14+ days.


If my sensor is greater than 20% different from my blood glucose meter either high or low, I change it out. Usually that happens around the third week. But 50 points away from a blood sugar of 300 is very different from 50 points away from a blood sugar of 100. Basically your blood glucose meter is considered "accurate" if 95% of the time it is within 20% of your actual blood sugar as measured by a lab. So I use that same standard for Dex.

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