Caused by degeneration of DA neurons in SN

EPI: affects> 1 mil. in US, peak age >60

DDx: idiopathic, multi sm. stroke (vascular), post CNS infxn (eg encephalitis), Drug-induced (anti-psychotic, antiemetics

SSx: bradykinesia, rigidity, tremor, postural probs

1. increase DA synthesis

2.Use DA receptor agonist

3. (-) DA metabolism

4. affect balance of dimished inhibitory DA effect vs. excitatory cholinergic neurons

peripheral decarboxylase inhibitor--> allows more plasma L-dopa to penetrate brain

does not X BBB

w/ L-dopa= Sinemet

carbidopa w/ L-dopa

used to Tx Parkinson's

allows L-dopa to m=be metabolized in the CNS

most effective controlling SSx

cost effective

chronic use--> drug induced dyskinesias and "on-off" motor fluctuations

DOC in older pts