Parkinson’s disease is a progressive neurological disease with symptoms varying for each patient. PD is characterized by four key motor symptoms, including: a resting tremor; slowness of movement (bradykinesia); muscle rigidity or stiffness; and postural instability (poor balance and coordination). Motor symptoms in Parkinson’s disease typically begin on one side of the body.
The disease also causes non-motor symptoms which often appear before a person experiences motor symptoms and can prove to be more troublesome for some. Non-motor symptoms include fatigue, excessive saliva, constipation, vision and dental problems, sleep disturbances, lack of facial expressions, orthostatic hypotension (low blood pressure when standing up), and mental health disorders such as depression, anxiety, and dementia. Researchers are still investigating these symptoms as some may be caused by other conditions or medication side effects. For example, dyskinesia is often thought of as a symptom of PD, but it’s actually a common side effect of Parkinson’s treatment.