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Symptoms and Signs of Parkinson's Disease

Doctor's Notes on Parkinson's Disease

Parkinson's disease (PD) is a chronic progressive deterioration of certain nerve systems in the brain, which affects movement, balance, and muscle control. In Parkinson's disease, certain brain cells deteriorate and result in a decline in the neurotransmitter dopamine, which leads to the symptoms of Parkinson's disease.

Early symptoms of Parkinson's disease may be vague and can include fatigue, depression, subtle decreases in dexterity, lack of coordination, aching or tightness in the calf or shoulder region, shuffling gait, decreased swallowing, constipation, sweating, sexual dysfunction, and sleep disturbances. The three key signs of Parkinson's disease are tremor (shaking) at rest, rigidity, and slowness in the initiation of movement (bradykinesia). Other symptoms of Parkinson's disease include postural instability, freezing when starting to walk (start-hesitation), flexed postures of the neck/trunk/limbs, altered mental status (usually occurs late in the disease), and short-term memory and visual-spatial function impairment.

Medical Author: John P. Cunha, DO, FACOEP
Medically Reviewed on 3/11/2019


Kasper, D.L., et al., eds. Harrison's Principles of Internal Medicine, 19th Ed. United States: McGraw-Hill Education, 2015.