I had 3 trays of Humalog in my fridge that I noticed the expiration date was coming up quickly. April 2010. I kinda/sorta noticed that recently my Humalog just did not seem to have the big bang/effect that it had in the pass. I asked the Walgreens Pharmaists, "How expired is expired? She explained that in most incidents that the product should last longer than the expired date as long as it was in the fridged.
But I was not trusting that response. So I ordered new trays of Humalog. And will be tracking the differance if any and will let you know of the outcome.
SO THE BIG QUESTION TO MY FELLOW READERS IS: Do you notice if there is a differance in effectivness in insulin if it is close to the expiration date?