Blood sugar varies wildly - Meter inaccurate ?

By PRP Latest Reply 2010-07-02 10:33:45 -0500
Started 2010-05-06 08:01:54 -0500

I was recently diagnosed as type 2 two weeks back. I am keeping track of blood sugar levels and noticed couple of things I cannot understand (Well, I don't understand most of it). Will there be huge variations in blood sugar levels in couple of minutes? For example to day I tested my after breakfast (one whole grain toast with 1 TBSP peanut Butter) . It was 149 and 2 minutes later I retested and it was 124. Is this normal or is my meter defective. I am using a Bayer Contour meter.
Sorry if this comes out as needy, but I don't know much and researching on internet has not given me satisfactory answers. Hopefully the knowledgeable members will have an answer.


9 replies

srhester 2010-07-01 09:36:45 -0500 Report

I've been using a Contour for several years now, but I had to buy a new one last night. Anyway, I checked my sugar when I got home and thought that seems about right. I wear an insulin pump and was in the process of changing it moments later. I checked my sugar again and it was more than 30 points different. My earlier meter returned results in 15 seconds and was much more consistent. This one returns in only 5 seconds. Further testing a few minutes ago, using the same blood from the same stick three different times resulted in 203, 217, and 231. My strips have not expired. Just wondering if this newer, faster meter has overall consistency problems or if it is just mine.

kdroberts 2010-07-01 09:53:21 -0500 Report

Every single meter has accuracy issues and the higher your blood sugar the wider the range for readings is. If your blood sugar was 200 then your meter would be classed as accurate if it gave any reading in the range 160-240. There is a push to get the accuracy standard tightened up to within 10% but it looks like it will be 15%. When you add in rapidly changing blood sugar levels then it becomes even more complicated. The main issue is you have to trust your meter because if you don't then you will just drive yourself crazy trying to second guess it. If you don't trust it you may have to look at a different brand or model.

PRP 2010-07-02 10:33:45 -0500 Report

I had the same issue couple of days back. The Bayer USB Contour meter I was having had an issue with the installed software and they sent me a new one to replace it. I tested both and found that from the same drop of blood new one read 132 and old one read 113. I tested the new one with the control solution and then tested again and old one gave 120 and new one 124. I had noticed this behavior with the old one too when I compared with Bayer Contour. Not scientific but I came to the conclusion that maybe the new meter has to be tested (I guess calibrated) at least once with the control solution.

PRP 2010-05-07 23:44:26 -0500 Report

—Update— Until now I was using the free Bayer Contour meter I got from the doc and today I received my new USB Contour meter I ordered. Now I am facing a new conundrum. I tested both meters one after the other with couple of seconds delay the new USB Contour is showing 10 less than the old meter. So I tested with the control solution and the difference was 7 again the old meter showing a higher value. Now I dont know which one to trust. I am thinking of taking both to my doc and want to compare the readings against the lab results. Is this the correct path to take or am I being paranoid? Is there anything else I should be doing ?


spiritwalker 2010-05-06 10:56:05 -0500 Report

If you feel your meter is off use your meter test solution and
check the meter. You might also check the battery. If you have
dropped the meter it could cause a problem. All meters can and will give different readings. Meters can be off by 10-20%.
Check your strips and make sure they are expired.
I hope this helps. Good luck.

petals 2010-05-06 10:25:01 -0500 Report

I have never had much luck using any of the Bayer products. I use One touch, and I love it. If this is your first meter, you might want to try others to see which one works best for you.

GabbyPA 2010-05-06 08:38:13 -0500 Report

Meters are fun, keep telling yourself that. LOL.

I guess my first question is why test two minutes apart? Unless you think a reading is in error? Sometimes I do that if I get a reading that I think is incorrect based on what I am expecting it to be.

Many things can cause the difference. It could be your first test was on a finger that was not washed thoroughly. You want to wash with warm water and soap every time. I do not use alcohol unless I am not able to get to water.

Another thing is that there are error margins in the meters in general. I forget the % that is allowable, but a 20 point difference is a little much, but not wildly off.

I have also noticed that I can take from different fingers and get different readings.

Unfortunately, it is not an exact science. It is a guide. When I get conflicting readings I write them both down and if it seems to be a trend, you can check with Bayer and see if they have any recommendations on what you can do to fine tune your meter. There should be a customer service number on the meter or in your paperwork.

PRP 2010-05-06 09:25:02 -0500 Report

You are correct regarding why test two minutes apart. I was not expecting that high numbers so I retested. In both cases I did wash really well using soap and warm water. But I did use two different fingers. Thanks for the suggestion of recording both and watching for a trend. Will definitely do that. This has happened twice. As I read somewhere two readings don't make a trend but might make a diagnosis. So I will go ahead and talk to Bayer Support. Thanks for the quick reply.

Next Discussion: SBLKFEM40 »