Freestyle Libre 2 - new user with confusing readings

I am only on day 5 of using the Libre 2 and up to now I have been really impressed and feel it is a game changer. Much more information and love being able to see trends, etc.

However - today the sensor readings have been really low, I’m getting lots around 3.3 to 3.9 when I don’t feel low at all. I have done finger prick tests to get a comparison and found that all readings today are roughly 2.5 mmol/l lower than the BG readings. In fact, looking at the daily graph it is so much lower than all previous days as well as being somewhat “flatter”, previous days all had spikes for each meal going up to 9 or 10 (something I wanted to improve upon but accepted that the results were in line with what I was getting just testing BG).

My latest reading on the Libre is 6.4 and BG is 8.9, which has been around this figure for the past hour, so is not rising rapidly or anything, therefore I would have expected the Libre to have “caught up” by now and be registering something similar?

I appreciate the reason for differences and a lag of even up to 30 minutes before the Libre reading is similar to BG but it seems unusually low today and always around about 2.5 lower than BG.

Has anyone else had similar experiences to this? I’ve read lots about faulty sensors, possible issues with the body reacting to the sensor filament, etc., but it seems odd this is happening after 4 days of perfectly reasonable readings? I’m now not sure what to do. If I believe BG over Libre then I would be looking to take some insulin to reduce the BG level, if I believe Libre then I would be perfectly happy and do nothing. I’ve checked my BG test strips and they are in date, although the meter is fairly old (a Contour Next USB meter) so could it be suddenly giving incorrect high readings?

Help! Any advice please from anyone with similar experiences? Thanks in advance!

Quick update - just tested my wife (who is non diabetic) using the Contour Next BG meter and get 4.9 which would be right for her. So I think I can rule out the BG meter being wrong, which leaves the question as to why the Libre is so much lower today.

MrsA2 said:

Sometimes, the sensors can fail and give odd readings. If you feel this is the case, call Abbott, they will do some checks and if it is failing, will replace it. Sometimes the sensors fail immediately, sometimes it takes a few days

Click to expand...

Thanks for the advice. If it’s still reading low tomorrow I’ll give them a call.

Hopeful34 said:

Just to say that if you ring Abbott, they will ask for three readings that you've taken where the Libre and finger prick test were different, like the 6.4 v 8.9. They're very good at replacing them if they're faulty.

Click to expand...

Thanks for the heads up, I’ve got at least 3 examples so I’ll get those together before I call them.

As an update I called Abbott first thing this morning and went through everything, giving them example readings showing the difference. There was no issue in sending out a replacement sensor, but of course there is a 5 to 7 working day lead time for this. All the customer service person said was that possibly the filament had bent meaning the readings were artificially low, but I guess it’s not possible to really say what the issue is.

I’ve read lots about sensor issues which is making me a bit uncertain about the whole system. I appreciate that out of the many sensors used a small failure rate translates into hundreds or thousands of individual problems, but even so, not having experienced any issues with BG test strips or meters before, it is a little unsettling. I really want to use this system to help improve my overall BG control so I’ll still keep an open mind for now and hope that this sensor is one of a very few failures for me.

Until my replacement sensor arrives I’ll be back to finger pricking again (the sensors are not yet on my repeat prescription so I don’t have any spare that I could use). Must make sure I always have some spare test strips in case I get issues in the future too!