Bad sensor

Quick question. ?.I am new to the CGM experience and noted that the current sesory I am wearing is reaaly off now for a few days stop this one before the week is up or continue in the week? I haven't been abke to wear longer than 7 days due to my sensitive skin.


Everyone is different, but for me, the first two days the readings are way off 20-100. Then they get better. Second week they start getting very close (0-10 off) and stay that way for about 8-9 days until they suddenly go off again (20-100) and then the ??? signal, which will come and go for a day or two until it stops working. I have to pay for this stuff so I usually wait about three hours to see if the ??? is permanent before changing.

BTW, I have an allergic reaction to most of the adhesives on the market (medical tapes), even the "hypoallergenic" ones. But I found one that doesn't cause a rash, Hypafix. Have to change the tape twice typically over the 14-17 days a sensor will typically last.

For your skin, try the 3M Tegaderm tapes, I think this particular one is of perfect size: You can put in on first, then the sensor on top and go through the tape. Works great for sensitive skin, though I wear it to make the device stick to me longer as the adhesive is longer lasting too.

The everyone is different thing is very true. I guess I'm lucky that it's off only the first day or two, then I get about 6 or 7 weeks of great readings, then it slowly gets worse. The last one I wore for almost 10 weeks. Finally took it off because I think I was getting a little too sore where it was located. Probably shouldn't have gone that long, but I was trying for a record or something. I'll probably stick to 6 weeks give or take.

EDIT: just had a thought, if it remains off for another day or two I'd call Dexcom and ask about replacement policies...

Tegaderm didn't work for me. Got a rash that looked like poison ivy. I don't have sensitive skin either.

If you are only getting 7 days out of one I would probably change it.

The sensor being off might not mean it’s a bad sensor. I find most of my outages come from large BG swings (50-100 points) and too frequent of calibrations. You want to make sure you are not over calibrating and the sensor seems to be much more accurate when your trends are more like the desert and less like the Rockies.

Sensors get more erratic when they are not secured well or are in areas where the sad kin flexes with normal daily activities. I get better readings and sensor life when I use the back of my upper arms. Can get three weeks before it falls off the cliff.

I have been having problems, too with last two sensors!!! I have been using the dex for two years and have not had any problems except for a few ??? show up couple times on day 14. I am feeling discouraged. I did receive my new receiver/transmitter in December. Everything working fine until this week??? I am a honeymooning type one, and my graph was all over the place… Usually pretty flat line and never straight up or straight down arrows. Maybe I am coming out of my honeymoon??? Also got hourglass and hardly any arrows next to bg number… Five days of this and I decided to change my sensor. This one is doing the same thing!! Help. Lol

I second Seth’s comment about calibrating too frequently. I used to check my BG and enter it into my Dexcom every time. That led to erratic readings, so i only entered it when it prompted me, and received better readings in return. Also, my Dexcom rep said that it should be accurate with 20% of your finger stick reading. For example, If your BG is 150, your sensor should be within 30 mg/L of that reading. That’s also assuming you’re a Dexcom cgm as well. And if the seven days are up, it might be time to change it (though many claim their sensors work longer). If it’s less than seven days, It could be defective, which might help get you a replacement. Hope that helps!