I have checked out a supplement available from the U.K. It is called Dopavite. Anyone reading this, if you are certain you have Parkinson's check this supplement out.
I recently found out that I was misdiagnosed and my slight head tremor was caused by taking too high of a dose of thyroid medication, and not Parkinson's. After a few weeks of my endocrinologist lowering my medicine for my thyroid my head tremor is gone. My neurologist diagnosed me as having Parkinson's and my only symptom was the slight head tremor and he asked me several questions and did a usual exam on checking reflexes. He never asked me if I had any muscle rigidity or muscle soreness at all. All I can say is, do not take one doctors diagnosis without doing a lot of homework on the disease and asking a lot of questions. I could have taken a Parkinson's medication for the rest of my life and had all kinds of side effects and not have had the disease to start with. Doctors are not infallable. Always follow your gut instinct. You know your body better than anyone else.