I found a couple of boxes of test strips in the back of my closet a week ago that had an expiration date back in 2013. I figured I would use them but do test strips go bad? It seems like since I have used these I have gotten some pretty wide ranges of BS readings that don't seem right. Just curious if anyone else has seen this happen. I use the One Touch strips and meter.
Yes they can go bad. Storage in high temperatures or humid conditions can make it worse.
If you doubt your strips or meter, compare with known good strips or meter (possibly different brands). "Control solution" is also out there but surprisingly not useful at the 20% level.
Yeah what Tim said.
Ok. Thanks. I’ll check them against a box I know is fresh.
I understand that once opened they can oxidize, which is the chemistry the rely on. Not sure how that impacts unopened strips.
Here sia bit on how they work:
The blood mixes with and hydrates the dry reagent, producing an enzymatic reaction that generates a chemical product. The amount of this product is proportional to the amount of glucose in the blood. Then, when the strip is inserted into a meter, the battery-powered device polarizes the strip’s working electrode. This sets in motion an oxidation process that generates a transient electrical signal, whose strength is proportional to the amount of the chemical product oxidized. The meter then applies an algorithm to convert the signal strength into a numerical value for the user.<="" blockquote=""> http://www.mdtmag.com/articles/2013/09/modeling-electrochemistry-blood-glucose-test-strips