Parkinson

Parkinson is most commonly used in reference to Parkinson's disease, a chronic neurodegenerative disorder that primarily affects movement. The term derives from James Parkinson, who in 1817 described the condition in An Essay on the Shaking Palsy, and the disease was later named in his honor. Parkinson's disease is characterized by motor symptoms such as resting tremor, bradykinesia (slowness of movement), muscular rigidity, and postural instability. Many patients also experience non-motor symptoms including sleep disturbances, mood changes, autonomic dysfunction, cognitive impairment, and sensory symptoms.

Pathophysiology of the disease involves progressive loss of dopaminergic neurons in the substantia nigra pars compacta, leading to disrupted circuits in the basal ganglia. Lewy bodies, abnormal aggregates of alpha-synuclein, are commonly found in affected neurons. Most cases are idiopathic, with age being the strongest risk factor; several genetic forms have been identified.

Diagnosis is primarily clinical, based on history and examination, with a good response to dopaminergic therapy supporting the diagnosis. Neuroimaging and other tests are usually used to exclude other conditions rather than to confirm Parkinson's disease.

Treatment aims to relieve symptoms and maintain function, as there is no known cure. Levodopa–carbidopa remains the most effective medication for motor symptoms. Other pharmacologic options include dopamine agonists, MAO-B inhibitors, and COMT inhibitors. Non-pharmacologic therapies—such as physical and occupational therapy, regular exercise, and speech therapy—are integral to care. In selected cases, deep brain stimulation or other surgical interventions may be considered for advanced disease.

Prognosis varies but is generally slowly progressive, with a typical course spanning many years. Ongoing research seeks disease-modifying therapies, biomarkers, and improved symptomatic management.