Pharmaceutical Treatment of Parkinson ’ s Disease The best outcomes rely on a handful of medicines and partnership among clinicians , patients , and caregivers

Parkinson’s disease (PD) is the second most common neurodegenerative disease. It affects an estimated 7 million people worldwide and will affect more than 14 million people by 2040. PD is diagnosed by the presence of progressive asymmetric bradykinesia and tremor (especially resting tremor) or rigidity, with a sustained response to dopaminereplacement therapy and the development of motor fluctuations and dyskinesia with long-term therapy. Early motor disability results from degeneration of dopaminergic neurons in the midbrain substantia nigra pars compacta, and dopaminergic medications are the foundation of therapy for motor disability. The critical driver of neurodegeneration in PD is intracellular toxicity of αa-synuclein (AS) oligomers. Over time, the core motor features worsen, and a fluctuating pattern of medication response, progressive gait and balance disorders, and nonmotor symptoms emerge, to the detriment of overall function and quality of life. Many changes reflect the spread of pathology throughout the brain over time.1 For decades, pharmacotherapy for PD has centered on restoration of dopaminergic activity in the brain. The miracle of levodopa reigns among the most important advances in the history of neurology. Treatment of patients’ nonmotor disability is less scientifically based and generally less successful. Management of patients with PD requires a practiced hand, and care provided by a neurologist carries a lower risk of nursing home placement, hip fracture, and death compared to that provided by primary care physicians.2 This review focuses on pharmacologic management of PD.