FDOPA PET and Nutritional Support in Parkinson's Disease

Intervention: IV NAC infusion: Dose: 50mg in 200ml of Dextrose 5% in Water (D5W), frequency: over one hour 1 x per week for 90 days ± 30 days AND Oral N-acetyl Cysteine - one 500 mg tablet 2 x per day (on days IV N-acetyl cysteine is not administered)

FDOPA PET diagnostic imaging to to measure dopamine function, serum measures of NAC concentrations, magnetic resonance spectroscopy (MRS) to measure inflammatory and oxidative stress markers, and neurological measures to assess clinical symptoms, in patients with PD who are given oral capsules plus IV infusions of NAC in addition to standard of care for PD for 6 months.