Douglas,
Welcome to what I have found to be a most beneficial forum.
If you are recently diagnosed, you might be well advised to check out the benefits of low-dose naltrexone(LDN) or low-dose dextromethorphan for neuroprotection. Check earlier posts by AshleyK or myself for details. There is substantial scientific support for the concept of these drugs of the morphinan class decreasing the inflammatory effects of microglial cells in the basal ganglia of the brain. This inflammation is thought by many researchers to be an important contributor to the loss of the dopaminergic neurons which occurs in Parkinson's disease. I mention this to you because of apparent benefit I have experienced with low-dose dextromethorphan.
After my Dx in 2001 and starting immediately with Sinemet and Amantadine, I started in 2003 taking 4-5 mg dextromethorphan from over-the-counter cough preparations every night at bedtime. This regimen, along with 900 mg Coenzyme Q10 daily, has resulted in very little progression of my symptoms with only small increases in Sinemet dosage.
Please understand that I am not recommending this approach; only sharing my experience.

Robert