Hello,
Like Robert, I have been taking a drug similar to DM. It is 4.5 mg of naltrexone or Low Dose Naltrexone. I have been taking LDN along with 600 mg of Q10 for the past 54 months in addition to my rather low doses of Sinemet and Mirapex. I don't think I've progressed over that time and I have not had to increase my PD meds.
The NIH has done some research on opioid type drugs at low doses which seem to mitigate neuroinflammation. See below.
Ashley

http://www.ncbi.nlm.nih.gov/pubmed/1...?dopt=Abstract

Neuropharmacology Section, Laboratory of Pharmacology and Chemistry, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina 27709, USA.

Inflammation has been increasingly recognized to contribute to the pathogenesis of Parkinson's disease. Several compounds are neuroprotective at femtomolar concentrations through the inhibition of inflammation. However, the mechanisms mediating femtomolar-acting compounds are poorly understood. Here we show that both gly-gly-phe (GGF), a tri-peptide contained in the dynorphin opioid peptide, and naloxone are neuroprotective at femtomolar concentrations against LPS-induced dopaminergic neurotoxicity through the reduction of microglial activation. Mechanistic studies demonstrated the critical role of NADPH oxidase in the GGF and naloxone inhibition of microglial activation and associated DA neurotoxicity. Pharmacophore analysis of the neuroprotective dynorphin peptides and naloxone revealed common chemical properties (hydrogen bond acceptor, hydrogen bond donor, positive ionizable, hydrophobic) of these femtomolar-acting compounds. These results support a common high-affinity site of action for several femtomolar-acting compounds, where NADPH oxidase is the critical mechanism governing neuroprotection, suggesting a novel avenue of anti-inflammatory and neuroprotective therapy.