I just started using Levemir on a daily basis. Although I've used only 2 of the 5 pens included in the package, my doc instructed to me to toss everything after 30 days. The expiration date on the package is 8/10/2010.
Does anyone understand this??
Supposedly insulin is no good 30 days after opening. So if you've used a pen, and it doesn't run out of insulin within 30 days, throw it away.
As far as the un-opened pens, I'd say that they are good until the expiration date. As long as no air gets to the insulin inside. But, since I don't use the pens (I'm on a pump), I'll leave this one up to the experts on the board.
But to reiterate, I've been told by all of my health care providers to throw away any insulin that is opened, after 30 days.