I am realy glad you all have came forward about all these side effects because i am on toprol XL 50mg a day for high blood presure and irregular heart beat it seems that my heart starts to beat irregular when my pulse gets into the 110 beats a minute to about 121 beats a minute and the Toprol sure is a life saver when it comes down to slowing my heart rate it will slow my heart rate down to about 85 beats a minute,but as for the rest of this medicine i have bad side effects too, i get realy bad chest pain on my left side around my heart area and go all around my chest left and right side and i have real bad panic attacks at night they are so bad that i cannot sleep, sometimes i feel my heart take off beating very rapidly and then back to normal it always realy scares me when this happens.thanks for you all posting your experiences about this Toprol drug it has realy eased my mind now I was realy thinking there was something realy wrong with my heart or body, now i know it's Toprol doing this too me thanks again.