The Critical 'I'

Read. React. Repeat.

Wednesday, April 14, 2004

EXPIRED ALKA-SELTZER
I was in need of some relief tonight, so I plop-plop-fizz-fizzed a packet of Alka-Seltzer. I took casual notice of the expiration date on the package: January 2004.

Who figures something like Alka-Seltzer would have an expiration date?

It didn't faze me; I went ahead and downed the dissolved remedy. It worked well enough. But curiosity got the better of me, and I checked later to see what, if any, ill effects I could expect from ingesting expired Alka-Seltzer tablets. According to the company:
We recommend that you discard any expired Alka-Seltzer product. It will not be harmful if ingested, but it may not be as effective in relieving your symptoms.
So I dodged a bullet there, seemingly. But unless I was experiencing a placebo effect, it felt like the stuff had done the job I expected it to do, in defiance of the expiration date.

I have a long-standing problem with having medicine cabinet items go bad; I guess I don't get sick often enough! Based on this Alka-Seltzer experience, I started to wonder if these go-bad dates really meant anything. I still have about a third of the box left, so I wanted a more definitive answer on whether I should keep it or toss it.

A little bit of research uncovered some compelling information that suggests that medicinal expiration notices are pretty much bunk:
First, the expiration date, required by law in the United States, beginning in 1979, specifies only the date the manufacturer guarantees the full potency and safety of the drug - it does not mean how long the drug is actually "good" or safe to use.

Second, medical authorities uniformly say it is safe to take drugs past their expiration date -- no matter how "expired" the drugs purportedly are. Except for possibly the rarest of exceptions, you won't get hurt and you certainly won't get killed. A contested example of a rare exception is a case of renal tubular damage purportedly caused by expired tetracycline (reported by G. W. Frimpter and colleagues in JAMA, 1963;184:111). This outcome (disputed by other scientists) was supposedly caused by a chemical transformation of the active ingredient.

Third, studies show that expired drugs may lose some of their potency over time, from as little as 5% or less to 50% or more (though usually much less than the latter). Even 10 years after the "expiration date," most drugs have a good deal of their original potency. So wisdom dictates that if your life does depend on an expired drug, and you must have 100% or so of its original strength, you should probably toss it and get a refill, in accordance with the clich?, "better safe than sorry." If your life does not depend on an expired drug - such as that for headache, hay fever, or menstrual cramps - take it and see what happens.
So, it appears you can keep that stuff for pretty much as long as you want. Even for aspirin, my bugaboo:
Consider aspirin. Bayer AG puts 2-year or 3-year dates on aspirin and says that it should be discarded after that. However, Chris Allen, a vice president at the Bayer unit that makes aspirin, said the dating is "pretty conservative;" when Bayer has tested 4-year-old aspirin, it remained 100% effective, he said. So why doesn't Bayer set a 4-year expiration date? Because the company often changes packaging, and it undertakes "continuous improvement programs," Mr. Allen said. Each change triggers a need for more expiration-date testing, and testing each time for a 4-year life would be impractical. Bayer has never tested aspirin beyond 4 years, Mr. Allen said. But Jens Carstensen has. Dr. Carstensen, professor emeritus at the University of Wisconsin's pharmacy school, who wrote what is considered the main text on drug stability, said, "I did a study of different aspirins, and after 5 years, Bayer was still excellent. Aspirin, if made correctly, is very stable.
Judging from the vinegary odor that emanated from the bottles I've thrown out over the years, I must have bought a lot of unstable aspirin.