I have been useing a Dexcom One CGM and I am really dissapointed with the accuracy.

[DenisR]

With the last batch which I have fitted since 11 May23 are so highly inaccurate I have pierced my fingers 50 times since 11 may.
Fitted a new sensor (to instructions) 11 may PM and had 3 high blood glucose and 1 very low warning overnight, continued useing on 12 May and decided could not rely on the readings.
Replaced sensor on 12 May and again very unreliable results when checked against my blood reading (Accu-Chek)
Replaced sensor 13 and again no reliable readings.
Replaced sensor on 14 May ( now wearing out my Accu-Chek) my reports tell me that there has been a -27% change in my performance to targets. I removed this sensor on 15May
I did not fit a new sensor until 17 May (from the same Lot and my blood readings are again causing me concern, as they are already showing higher than expected readings.
In my experience the Dexcom one is really not fit for purpose and I would advise anyone with Type 1 Diabetes do not rely on the Dexcom one to administer Insulin from the readings, as this could lead to an overdose.
I originally started on Dexcom 6 and the results on this were not highly accurate, however it had a calibration capability so when yo wanted to check the accuracy, a blood test was done and the Dexcom 6 calibrated based on the blood test.
Dexcom one does not have calibration capability and in my view is worthless without it.

 

[Sally71]

Have you tried contacting Dexcom? It might be a faulty batch, and their customer services are usually very helpful.
The other thing worth noting is that different CGMs seem to suit different people better. We thought Libre was OK but find Dexcom way more accurate. We use the G6 because it links with the pump, but have stopped checking the accuracy because almost every time we did it was within 0.2 of the finger prick reading, and the only time it wasn’t was when BG was dropping rapidly. There’s bound to be a bit of a lag then, and once the BG had stabilised the accuracy was back. There are other people who don’t find it as accurate as we do though, and you get the same with Libre, some people love them and some people find them next to useless.

 

[everydayupsanddowns]

Sorry to hear you are having a frustrating time with your Dexcom.

Sometimes sensors can take a few days to settle - and some sensors have a reputation for reading ’off’ for the first 24 hours or so, so perhaps it would be worth seeing if a sensor settles after a few days?

Additionally, you need to bear the sensor lag n mind when comparing against capillary glucose values (which react to changes in BG much more quickly than the interstitial glucose values that sensors are reading.

But yes, I agree with @Sally71 - do give Dexcom a call and ask about replacement sensors where you have had ones that have not performed up to standard.

 

[ChrisH22]

I agree with Denis, the accuracy of the Dexcom One is way off and means that my T1 wife is having to recheck each reading against her Accuchek. The inability of D1 to be calibrated means that the single hi and low alarms have become a nuisance rather than informative. Here in Scotland the NHS only prescribe G6 if you are pregnant (my wife is in her seventies!) and they haven't heard of G7. We tried G7 initially, paying for them ourselves, and they were reliable, accurate, convenient and capable of being easily calibrated by the user if needed - we thought half a unit was excessive, with D1 variations of 3 or 4 is common.

 

[Lucyr]

Perfectly accurate for me. Different things suit different people though.