I keep fresh aspirin in the house, gets replaced as it expires, about every 2 years. I ended up foisting it on my mother in law a few months ago. Happily it turned out that she was not having a heart attack, and that the results of a heart cath and echocardiogram showed the same results as a few years ago.
The end result was her medicine was determined to be not correct and she was taken off of some, which has significantly improved her health and brain function. Her "words with friends" (Scrabble) scores went up, and she is beating me regularly. I have had to step up my game.
Phil