I have the same experience with Alvogen Adderall! I was given this instead of the usual manufacturer Teva by my pharmacy. I called today to see if they will fill my Rx with that same brand and they said yes. I will go to another pharmacy.
It does NOT work for me. I can take an Alvogen Adderall tablet and instead of helping me to focus it makes me feel as though I need a nap!
In my opinion, based on my experience Teva is the best brand.