Diagnosis and Initial Management of Parkinson's Disease

Abstract
A 62-year-old man presents with an intermittent tremor in his left hand and some vague discomfort in the left arm. Physical examination shows a minimal rest tremor in the left hand that disappears with use of the limb, mild rigidity at the left wrist and elbow, slowness of finger tapping with the left hand, and decreased arm swing on the left while walking. How should he be evaluated and treated?