What happens to expired Tamiflu?

December 17, 2009 4:10 PM

What happens to expired Tamiflu?

I think I am getting the flu. My doctor's office is closed for the night. I have four Tamiflu capsules left from a prescription I got on Feb. 7, 2001, making it close to 9 years old (though likely older; I have no idea how long it sat on the shelf in the pharmacy before I got it). I have read that the shelf life of Tamiflu was recently extended to 7 years. So, is my Tamiflu ineffective now? Or toxic? Is it better than nothing tonight or should I just wait until tomorrow morning to go see the doctor? I would like to head this thing off at the pass, if at all possible.

I plan to see my doctor tomorrow either way, so I would switch to the fresh stuff if it were prescribed to me tomorrow. This is just for tonight.

Please, don't just tell me that it may be useless or toxic now. I know that. I'm trying to determine which it is, and if there's any advantage or disadvantage to taking it.

posted by amro to Health & Fitness (7 answers total)

This has been asked before.
posted by rancidchickn at 4:50 PM on December 17, 2009

Response by poster: rancidchicken, I am asking about Tamiflu, not Tylenol.
posted by amro at 4:52 PM on December 17, 2009

Very, very few medications actually become toxic as they age (tetracycline antibiotics are one of the few exceptions). Most simply slowly become inert. Whether the old Tamiflu would be effective or effective enough to be worth the risk of side effects I can't say. It's likely no one can, in fact, since long-term shelf life studies are pretty rare.

The prior thread you disregarded had a best answer that addressed the topic in general. The linked Medscape article requires a free registration, but if you hit it from a Google search results page it should work without registration.
posted by jedicus at 5:10 PM on December 17, 2009

Best answer: I have a graduate degree in pharmacology and have seen drug stability data that has been presented to the FDA. It's extremely unlikely that the FDA would approve a drug that turned into poison after sitting on the shelf a little longer than normal. If the normal shelf life is 7 years, stuff that is 9 years old should be very close to normal effectiveness, especially if it's been kept dry and cool. I would take a normal dosage without a second thought
posted by exogenous at 5:10 PM on December 17, 2009

Best answer: Some FDA testing has found lots of Tamiflu that will be good five years after the original expiration date. Seems like it keeps its potency well.
posted by zsazsa at 5:11 PM on December 17, 2009

Response by poster: Thanks folks, I took it!
posted by amro at 7:13 PM on December 17, 2009

Yep, it looks like Tamiflu keeps its potency all right, but since there's some evidence that its potency is not much better than a placebo and its long term side effects are unknown, I'd say its worth is not much less than it already was.
posted by kch at 8:00 PM on December 17, 2009