Disease	History	Physical examination	Work-up	Treatment options
Idiopathic Parkinson's disease	Gradual onset; tremor, gait disturbance, slowed movements	Resting tremor (affects limbs more than head)	Physical examination is best	Levodopa, dopamine agonist, COMT inhibitor, selegiline (Eldepryl), surgery
		Cogwheel rigidity (affects limbs more than neck or spine)
Drug-induced parkinsonism	Previous exposure to a drug such as metoclopramide (Reglan) or haloperidol (Haldol)	Similar to idiopathic Parkinson's disease	History and physical examination are best	Discontinue offending drug or change to another drug if possible
Essential tremor	Present for many years, positive family history	Tremor with arms raised (postural), head involved	Physical examination is best	Beta blocker (e.g., propranolol [Inderal]), primidone (Mysoline), anticholinergic drug, surgery
Multisystem atrophy	Parkinsonism with autonomic system dysfunction, dysarthria	Orthostatic hypotension, skin changes (e.g., seborrhea)	Physical examination is best	Levodopa trial, measures to control/reduce blood pressure (e.g., salt-intake reduction, support stockings, midodrine [ProAmatine])
Progressive supranuclear palsy	Difficulty reading or driving, stiffness, bradykinesia, cognitive or behavioral changes	Gaze palsy (down more than up), axial rigidity (affects neck and spine more than legs)	Physical examination is best	Levodopa trial, vision aids, physical therapy
Huntington's disease	Involuntary movements, cognitive or behavioral problems	Chorea, loose tone, early dementia	CT or MRI studies of head to measure caudate nuclei	Neuroleptic drugs (e.g., haloperidol)
Normal-pressure hydrocephalus	Urinary incontinence, memory or cognitive problems	Dementia with frontal lobe features, festinating gait	CT or MRI studies, lumbar puncture	Evaluate for ventriculoperitoneal shunt
Multiple lacunar strokes	Stepwise neurologic complaints and functional loss	Focal findings, asymmetric sensory or motor loss	CT or MRI studies of head	Acetylsalicylic acid (aspirin), risk factor control (e.g., diabetes, hypertension, high lipid levels)
Pugilistic (post-traumatic) parkinsonism	Repeated head trauma (e.g., in boxers)	Bradykinesia, evidence of previous trauma	CT or MRI studies of head	Levodopa trial, selegiline trial
Depression	Dysphoria, poor appetite, disturbed sleep	Depressed mood and affect	Appropriate tests to rule out coexisting organic disease	Antidepressant drugs (selective serotonin reuptake inhibitors, tricyclic antidepressants, etc.)