- Progressive depletion of dopamine from substantial nigra, which occurs for unknown reasons
- Secondary PD assoc w/many conditions, including: meds→ antipsychotics, antiemetics; repeated head trauma→ boxers; toxins→ MPTP; vascular dz; Lewy body dementia
- Tremor occurs at rest and w/activity
- Pill rolling tremor of hands
- Sometimes head bobbing tremor
- Difficulty starting and stopping movements
- Balance and gait problems
- Difficulty swallowing, sometimes assoc w/aspiration
- Sometimes cognitive decline, which occurs after motor symptoms develop
- Symptoms are progressive
- Characteristic pill-rolling tremor
- Findings are bilateral, though typically worse on one side
- Shuffling gait w/limited arm swing and flexed posture
- Difficulty getting up and starting movement
- Difficulty turning