tester past its use-by date?

[melancholic]

ive owned my original ez tester for around 15/16 months. and while ive only tested under 20 pills (probably around the ten mark) its had a rough time, the liquid has leaked, its been shaken about etc.
in any case last time i used it a couple months ago, it worked fine.
yesterday i tested some pills, i shaved 3 different pills, each on two different sides, and there was not a single reaction. i was astonished as ive never tested a pill that hasnt reacted in one way or another.
so i obtained a E1 and E2 tester, and tried it out. once again i shaved 3 pills, 2 sides each, and each scraping went purple instantly. the E2 tester went purple also.
why did my tester give no reaction? is it possible its just too old?

 

[mashead testing]

It sounds like its out of date yes, I think the advised length of time that they stay good for is about 6 months although if kept in good conditions then maybe even a year or so.
I have a marquis reagent that is about 15 months old and that still works correctly.

 

[johnboy]

what bob said. testing kits don't have official expiry dates, but i think they should. they might lasy a year or more, bnut they also can go off sooner. do you really want to bet yor life on it?

 

[catfud]

Its a good idea to keep little bits of well-known pills around as a standard of comparison. Once when I got a weird reaction testing a pill, I was able to run a test on some bits of an old pill I saved, and determined that the EZ-Tester we were using was bad.
I often split pills in half before going out - and keep the "kibbles and bits" for test comparisons.