ashleyk,
Please see Carolyn's thread on Can Sound Slow Parkinson progression. Towards the end is a statment that says "Findings from a small study (with only 80 participants) at the University of California, San Diego, suggest that taking 1,200 mg per day of coenzyme Q (CoQ10) can also help slow progression of the disease in its early stages, although these are very high doses and quality supplements can be quite expensive. Before we can say for sure that CoQ10 helps, the results must be confirmed in larger studies."

Hope this helps

GregD