A 2016 article reported many studies show a higher prevalence of H-pylori infection in Parkinson’s patients; however, the final hypothesis was H-pylori interferes with absorption of Parkinson’s medications. Malabsorption may be a factor, but can develop in any chronic infection with immortal bacteria and/or parasites, during the infectious cascade. The article overlooked that H-pylori can migrate or metastasize to the brain to cause Parkinson’s. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4828559/

Studies in Brazil found low dose doxycycline was effective in treating Parkinson’s disease and reducing motor fluctuations, in mice. Dr. Merchant treated a Parkinson’s patient with chlamydia pneumonia with a low-dose macrolide, for six years, and saw improvement in symptoms and motor fluctuations.

More than one pathogen or combination of pathogens may cause Parkinson’s disease. Treatment of Parkinson’s disease, with low-dose antibiotics directed at infectious pathogens, is not ordinarily considered in the treatment of Parkinson’s disease.