I asked my neurologist about taking something to help me better focus or concentrate, possibly an ADHD drug as I now feel that I may have always had this problem & now with the PD, my meds & extreme tiredness, my mind is in a constant fog. I have also been diagnosised with OCD & anxiety disorder. She perscribed Methylphenidate, 5 mg tablets, however to take only 1/2 a tablet just once a day in the morning, she said that I could increase to one tablet after a week. She knows that I hate meds, fought taking anything for years, but finally had to in order to function. Whenever she suggests something new, I say no or maybe I'll try just 1/2 of the smallest dose. Anyways, just started taking this 2 days ago & my mind is in over-drive! I sat down to put a few of my thoughts into words as you all suggeted for documentation for social security & practically wrote a book. The next day (after working an 8 hour day, after which I usually just nap or zone out) I decided to try & balance my checkbook by going back through years of statements. My neurologist had said this had been found to be helpful for movement in PD patients, well the past few nights, I have slept much better. I usually constantly awake in pain or because I can't move my arms or legs, no problem the last few nights though. And....no nap needed the past few days, much less yawning (usually constant) & no dozing off when working or driving. Not sure, but think this is an ADHD drug, I am afraid to google it & find out about some horrible side effect. Someone else do it, but break it to me gently, if you find it so.