I realize this is an old question but Im providing an answer for future reference & because I dont see any other answers posted. I recently pulled a box of nebulizer vials from my medicine cabinet in the middle of the night when I couldnt breathe & I did a nebulizer treatment & felt much better & much to my surprise, had very little shaking & heart racing. As I began to put everything away, I noticed that the box said Xoponex & not Albuterol like I was expecting. I havent had Xoponex prescribed to me in 3 yrs, which would have made it 2 yrs expired! Yet that nebulizer treatment was FAR more effective than any other one I had done in that past week while really sick & my experiment didnt stop there, I tested the waters a few more times & its true I prefer expired Xoponex over non-expired Albuterol, thats terribly sad!
Ok scratch that...I can now see many people posted an answer to this question Lol...Im not sure why I was unable to see the responses until I posted mine hmmm...strange??