Medical Treatment of Parkinson’s Disease

Parkinson’s disease (PD) is a neurodegenerative progressive disorder. The rate at which the disease progresses to disability varies from one individual to another, with uncertain functional prognosis at the time of diagnosis [1–6]. Nonmotor symptoms have been identified and may precede the motor manifestations of PD by decades. Nevertheless, clinical diagnosis continues to be based on the identification of the cardinal motor signs: bradykinesia, resting tremor, rigidity and postural instability [7]. Generally, in the early stages symptoms are usually mild, with minimal or no disability, and anti-PD medications provide an efficacious and constant control of motor symptoms and signs throughout the day [1–6, 8]. However, after this period, most patients experience a loss of effectiveness of anti-PD medications, as expressed by shorter duration of symptomatic effect or insufficient control of motor signs of the disease. Usually at this stage motor complications arise, characterized by motor fluctuations and dyskinesia, forcing a new treatment strategy to be implemented [8–19]. In general, 10–12 years after treatment onset, patients experience a worsening of axial signs, translated by imbalance and falls, often followed by cognitive decline and dementia [20–22]. The management of individual patients is complex, requiring careful consideration of a number of factors, including age, disease stage, years of disease duration, degree of functional disability, level of physical activity, and productivity. Currently, there are several therapeutic approaches in PD: pharmacological, nonpharmacological, and surgical therapies. This chapter will address the medical treatment of PD.