Ubiquinol in Parkinson's Disease: Safety, Tolerability, and Effects Upon Oxidative Damage and Mitochondrial Biomarkers

Inclusion Criteria: * diagnosis of PD according to the Untied Kingdom (UK) Brain Bank Criteria, and confirmed by a Movement Disorders neurologist; * age 40-75 years; diagnosis within 5 years of study participation; * PD medications able to remain at stable doses in the opinion of the enrolling investigator; * able to undergo MRI; * absence of significant medical, psychiatric, and other neurological disease; * absence of dementia and Mini-Mental State Examination (MMSE) \> 26. Exclusion Criteria: * failure to meet diagnosis by above criteria; * time since diagnosis \> 5 years before study participation; * PD medications not predicted to remain at stable doses in the opinion of the enrolling investigator; * unable to undergo MRI; * unable to comply with informed consent process; * presence of significant medical, psychiatric (including major depressive disorder) or other neurological (including epilepsy, brain tumor, stroke) disease; * diagnosis of dementia and/or MMSE 26 or lower; * possibility of pregnancy (negative test required in women of childbearing age); * taking medications including antipsychotic agents and dopamine- blocking anti-emetic agents; * taking Coenzyme Q10; * participation in another clinical trial within the last 3 months.