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Dexcom readings

K

KnittingGirl

Member
Hi. I finally got a Dexcom one on Monday. However the readings on the senor seem to be 2 higher than my glucose meter. I keep getting high readings when my sugar is in range and no warnings when my sugar drops. Is this normal? I have used three different glucose machines to double check. Thanks.
 

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KnittingGirl said:
Hi. I finally got a Dexcom one on Monday. However the readings on the senor seem to be 2 higher than my glucose meter. I keep getting high readings when my sugar is in range and no warnings when my sugar drops. Is this normal? I have used three different glucose machines to double check. Thanks.
Click to expand...
I'm a G6 user but don't think this is normal, though I do sometimes find that my sensor reads low for the first 24 hours while "settling in". I suggest you ring the dexcom 24 hour helpline for advice. (Well, it's 24 hour in NZ)

uk.store.dexcom.com

I'm having an issue while using my product(s). Who do I contact? | Dexcom

For technical support, please contact us on 0800 031 5763. For product troubleshooting or replacement enquiries, please complete a Product Support Request.
uk.store.dexcom.com uk.store.dexcom.com

I wouldn't worry about a 10% difference, but yours is more like 20%. Also be aware that the graph needs to be flat when you check?
What's the discrepancy like at low levels when you are entering hypo territory?

Edited to add: if it was just one machine I'd argue that they could both be 10% out from the mid-point of 9.8? But missing out on low alerts is a real problem.
 
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My experience is the same as @EllieM For me, the graph for the first 24 hours of a new sensor looks like an earthquake trace bouncing all over the place! After the first day I find it very accurate but the sensor I have on at the moment I calibrated. I don't know if the calibration helped but the readings are very close to my glucometer now (but that may have been the case even if I didn't calibrate, I'll never know). But, yeah, I'd ring the helpline
 
EllieM said:
I'm a G6 user but don't think this is normal, though I do sometimes find that my sensor reads low for the first 24 hours while "settling in". I suggest you ring the dexcom 24 hour helpline for advice. (Well, it's 24 hour in NZ)

uk.store.dexcom.com

I'm having an issue while using my product(s). Who do I contact? | Dexcom

For technical support, please contact us on 0800 031 5763. For product troubleshooting or replacement enquiries, please complete a Product Support Request.
uk.store.dexcom.com uk.store.dexcom.com

I wouldn't worry about a 10% difference, but yours is more like 20%. Also be aware that the graph needs to be flat when you check?
What's the discrepancy like at low levels when you are entering hypo territory?

Edited to add: if it was just one machine I'd argue that they could both be 10% out from the mid-point of 9.8? But missing out on low alerts is a real problem.
Click to expand...
Hi. I’m on day 5 but wondering if I’ve not put it on properly. I might change it and see if there is any difference.
live sent a request to Dexcom so hopefi they will help.
 
plantae said:
My experience is the same as @EllieM For me, the graph for the first 24 hours of a new sensor looks like an earthquake trace bouncing all over the place! After the first day I find it very accurate but the sensor I have on at the moment I calibrated. I don't know if the calibration helped but the readings are very close to my glucometer now (but that may have been the case even if I didn't calibrate, I'll never know). But, yeah, I'd ring the helpline
Click to expand...
I’m on day 5 and it’s been like it since I put it on. I’m thinking of putting a new one to see. I cant see where to calibrate it? Can you with dexcom 1. sorry all new to this.
 
Hmm,just found this on the dexcm site about the accuracy of the ONE

How accurate is Dexcom ONE vs. blood glucose meter | Dexcom

How accurate is my Dexcom ONE compared to my blood glucose meter? Dexcom CGM systems provide much more information for users. Read more.
www.dexcom.com www.dexcom.com
Looks like within 1.1 if less than 4 and 20% if over that?

Frankly, this is why you need calibration. (in my opinion)
And my google fu is totally failing to find out whether the ONE can be calibrated....
Is there a calibration button on your dexcom app settings @KnittingGirl ?
 
Morning All

It is not possible to calibrate Dexcom One. The only way to calibrate is to use an App such as Shuggah.

I used Dexcom One for 3 months. Some of the sensors were excellent, others not so. When I called Dexcom they told me 20% difference between finger prick and Dexcom was acceptable. Not sure if that was just for Dexcom One or all Dexcom.

I would give Dexcom a call. They should send you a replacement

Good Luck
 
There's never going to be any accuracy comparing a CGM to a blood glucose meter, a CGM is working on a 20 min lag and using predicted outcomes, best advice is to ditch the glucose meter otherwise you're just creating more stress for yourself. I only use a meter if I don't trust the CGM as feeling low/high and need verification for driving/exercise, sometimes a CGM can't catch up with rapidly falling/rising levels and that's where a meter is best for a quick spot check.
 
I agree - CGMs (like Decom & Libre) are never going to be totally accurate compared to a finger prick as they measure blood from the interstital fluid surrounding the bloodstream, instead of from the bloodstream itself.

I've recently started using Dexcom One as I was getting so frustrated with my Libre sensors being WAY inaccurate and not always working. One great plus point about the Dexcom app is that you just have to open the app and hey ho, there's your reading! However, there's nowhere as much information on the app as there was on the Libre app & you can't seem to add event notes (e.g. insulin dosage, exercise). Is this a known issue? Also, the Dexcom app on my Samsung A20 is battery-draining.

David
 
However, there's nowhere as much information on the Dexcom One app as there was on the Libre app & you can't seem to add event notes (e.g. insulin dosage, exercise). Is this a known issue?

Anyone know the answer to this, please?

David
 
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