hi, I just wanted to let you know, you are not alone.  I have a horrible time on the extended release tablets.  #1, they arent extended for me.  I guess that must be due to digestive issues, no one knows, not my dr, not the pharm.  But most importantly is that my doctor believes me, and that he knows extended release just isnt a good option for me.  I wish it were, it certainly would be more convenient!!  One of the first stimulants I ever tried was Concerta, I think that lasted about 2 days, because it wore off much faster than it was supposed to and the rebound/anxiety/oversensitivity/and such, was so bad, I couldnt even watch my kids go up or down steps.  They all can affect you different.  The brain is just too complex to fit a mold, that the drug manufacturers try to sell us on.  I also just went through a trial of vyvanse and it was a 3 week hell.  For me, Shires dosing info was so off of "my" marks that, like I said, it was my own personal hell for 3 weeks, until I went back on Adderall IR.  Going back on Adderall IR was an overnite change.  I was so relieved and I couldve cried.  By the way, I also have more BP and HR issues on the extended release meds too.  Hope you do better, why did you switch from Ritalin, when you were doing great??  If I ever get that lucky on a med, I can tell you, I will follow the old saying, "dont fix it if it aint broken!!"  Take care, have a great holiday!! Stacey