Jonathan, I am 47. I took Amantadine along with Eldepryl for about 4 years. My initial medication after diagnosis w/PD was only Eldepryl, then Amantadine, Parlodel, and Sinemet CR were added in that order. Amantadine worked very well for me for over 3 years (especially in controlling tremor) and I was much healthier (re common colds and the flu) than my wife and son. However, I think that Amantadine, especially when combined with Eldepryl, acts like an "upper." My Amantadine was reduced from 3 x 100 mg to 2 x 100 mg per day when Parlodel was added. Late last year, I began to have severe problems with insomnia. I think that the lack of sleep began to affect my thinking. After I quit taking Amantadine, my Eldepryl was reduced from 2 x 5 mg to 1 x 5 mg per day, and Tasmar was added to a reduced level of Sinemet. I now sleep much better. I think the increased sleep will probably have a long term beneficial effect on my life with PD. I did have the worst "cold" that I've had in several years after stopping the Amantadine. The tremor in my hands and arms (primarily right side) seems to have increased slightly since I stopped taking Amantadine. I would recommend that you not take Amantadine later than noon. My current Sinemet CR use is 1/2 of 50/200 CR three times/day. My Tasmar use is 2 x 200 mg/day. I take Parlodel (4 x 2.5 mg/day). I still think Parlodel is working for me, because when I forget to take the 2nd dose, I begin doing things very slow at work. My neurologist told me that it's ok for me to take an extra Parlodel when I'm having a bad PD day.