Glucose test strips are expensive. Are you wasting money if you throw away expired strips? Are they still accurate if you use them after they have expired? These are important questions to ask if you cannot afford new test strips, or want to use old ones.
A company named Glucomart performed some tests to help answer these questions. The design and results of their study are shown below.
- They used test strips from different manufacturers that had been expired for 1, 2, 3, 4, or 5 years.
- The expired strips were compared with the same brand unexpired strips.
- Three control solutions were used: normal, high, and low concentration glucose solutions.
- Test trips were tested three times in each control solution.
- Statistics were used to test the accuracy of each strip.
- The brands tested included:
- Accu-Check Aviva Plus
- Accu-Check Compact
- Bayer Breeze 2
- Bayer Contour
- Bayer Contour Next
- FreeStyle Insulinx
- FreeStyle Lite
- Nova Max
- One Precision Xtra
- One Touch Ultra
- One Touch Ultra Blue
- The accuracy of the test strips depended on:
- The brand of the test strip.
- The length of time since expiration.
- There results were as follows:
[thumbnail target=”_self” alt=”Accuracy of the test strips by brand ” src=”https://diabeticfaq.com/wp-content/uploads/2016/04/Test-strip.png”]
- There was no significant difference between the accuracy of unexpired strips and those that had been expired for up to 1 year.
- Most strips that expired 2 years previously were accurate, except for Precision Xtra:
- Precision Xtra strips that expired 2 years ago were not accurate or precise. Those that expired 3 years ago gave false low readings.
- Most test strips that expired at least 5 years ago were less precise and accurate.
- They sometimes gave variable readings.
- The results of most “normal” readings were 10–15% lower than with unexpired strips.
- Four brands were still accurate after 5 years. Bayer Breeze 2 were most accurate, followed by One Touch Ultra. TrueTest and TrueBalance also remained accurate.
- Most strips can be used safely within 1 year of expiration.
Notes of caution
- You should always use discretion if using expired test strips.
- This was a small study, and a larger-scale trial might give different results.
- If you are planning to use expired strips, always use control solutions and test for accuracy before use.
- Test strips in open vials should not be used after 6 months.
- If you think that your strips are inaccurate do not use them. Contact your physician or the test strip manufacturer for advice.
- It is possible that your manufacturer will replace your expired test strips.
- If you wish to use expired Accu-Check Aviva Plus test strips you must get a “black code chip”. It is free from the manufacturer, and is available on their website. You will get an error code without using this chip.
- This information is not provided to guide your treatment or help cure, treat, prevent, or diagnose any disease.
- You should always follow your physician’s advice.