Are your drugs *really* expired?

Ever wondered if those acetaminophen you found in the drawer with a 1990 expiration date are any good? Or if they could kill you?

I came across this study
http://www.health.harvard.edu/staying-healthy/drug-expiration-dates-do-they-mean-anything
(which is one of many giving the same information - but of course, not *enough* information for you to really make any decision on specific drugs in your house).

They referenced a U S Army study, which you can find online (but it looks like you can’t get it without either being a military/government person, or perhaps paying for it).  This was important to the Army since it could potentially mean savings of multiple millions of dollars in costs (not having to replace their reserves so often).

Nevertheless, I found a separate study:
http://archinte.jamanetwork.com/article.aspx?articleid=1377417
which gave some good information on some specific drugs. One thing is that Acetaminophen seems to have a long shelf life. They looked at some drugs that were at least 28 years(!) past their 'expiry' date and the 250mg Acetaminophen tablet still had 249.2mg of active ingredient!

Various caveats on temperature and humidity of course – and some good rules of thumb (if it smells bad, or is starting to ‘crust over’ or change colour then consider it to be going bad).

If you find any other good sites with more information please let me know.