Using expired test strips can save you a lot of money, but are they accurate? This is an important question for diabetics who can not afford new test strips or for those who want to know their old test strips are still safe. We tested several brands of test strips that had been expired between 1 and 5 years and found that accuracy depended upon the length of time since expiration and the brand of test strip. Test strips were tested with brand specific controls that had at least 6 months until expiration. Test strips were tested 3 times per each control solution (normal, high, low) and averages, standard deviations, and %RSD were used to determine accuracy and precision. Brands of test strips tested included: One Touch Ultra, One Touch Ultra Blue, FreeStyle Lite, FreeStyle, FreeStyle Insulinx, Accu-Chek Aviva Plus, Accu-Chek Compact, Bayer Breeze 2, Bayer Contour, Bayer Contour Next, Advocate, Element, Embrace, Liberty, Precision Xtra, TrueTest, TrueBalance, and Nova Max. Results are for educational purposes only and are not intended to diagnose, treat, cure, or prevent any disease. Please follow the advice of your physician.
Expired Test Strips Data
Test strips that had been expired for 1 year or less were not found to have a statistically significant variation in readings compared to unexpired test stirps. The majority of test strips at the 2 year mark were within the control solution range with the exception of Precision Xtra. Precision Xtra test strips that had been expired for more than 1 year were very slow at absorbing the control solution and readings were neither accurate nor precise. At three years past expiration Precision Xtra test strips read on average 102 below for high controls and read low (<20 mg/dL) for low controls.
Test strips that had been expired more than 5 years tended to have lower accuracy and precision. At the 5 year mark, normal controls (110-150 mg/dL) read on average 15 points lower than non-expired test strips and had occasional erratic readings. Four of the nine brands tested at the 5 year mark were within the control solution range, these included: One Touch Ultra, Bayer Breeze 2, TrueBalance, and TrueTest. Bayer Breeze 2 provided the most accurate results for test strips that had been expired for more than 5 years, with One Touch Ultra being the second most accurate.
Based on our results most test strips can be used safely if they have less than 1 year past expiration. This is, however, a very small study and results may differ with larger sampling sizes. Please use discretion if you choose to use expired test strips. Always use control solutions and test using non-expired test strips to make sure they provide similar results. Test strips in vials that have been opened can give erratic results if used past 6 months of opening the vial. If you feel that your test strips are providing inaccurate results, whether it they are expired or not, stop using them immediately and contact your physician and/or the manufacturer of the test strip. Manufactures will occasionally replace expired test strips.
Accu-Chek Aviva Plus test strips do not work once they are expired unless you use a permanent black code chip (available for free on Accu-Chek’s website). Expired Accu-Chek Aviva Plus test strips will have an error code if used with white code chips that come with them. To use Accu-Chek Aviva Plus test strips after they expire you must have a black code chip in the meter.
We tested Glucofilm test strips from 1993 (a discontinued test strip) and there were no results above 20 mg/dL.