Parkinson's Disease is a progressive nervous system disorder that affects movement. It develops gradually, sometimes starting with a barely noticeable tremor in just one hand. Although tremors are the most well-known symptom, the disorder also commonly causes stiffness or slowing of movement.

In the early stages of Parkinson’s disease, your face may show little or no expression, and your arms may not swing when you walk. Your speech may become soft or slurred. Parkinson's disease symptoms worsen as your condition progresses over time.