Parkinsonism is a progressive neurological disorder characterized by bradykinesia, muscular rigidity, resting tremor, and impaired balance. It can be caused by idiopathic Parkinson's disease, vascular issues, certain drugs that block dopamine, or dementia with Lewy bodies. Treatment aims to increase dopamine in the brain and involves levodopa, dopamine agonists, MAO inhibitors, COMT inhibitors, amantadine, and anticholinergic drugs.