L-dihydroxyphenylserine (Droxidopa): a new therapy for neurogenic orthostatic

Abstract Neurogenic ortho-static hypotension results fromfailure to release norepinephrine,the neurotransmitter of sympa-thetic postganglionic neurons,appropriately upon standing. Indouble blind, cross over, placebocontrolled trials, administration ofdroxidopa, a synthetic amino acidthat is decarboxylated to norepi-nephrine by the enzyme L -aro-matic amino acid decarboxylaseincreases standing blood pressure,ameliorates symptoms of ortho-static hypotension and improvesstanding ability in patients withneurogenic orthostatic hypoten-sion due to degenerative auto-nomic disorders. The pressoreffect results from conversion ofdroxidopa to norepinephrine out-side the central nervous systemboth in neural and non-neuraltissue. This mechanism of actionmakes droxidopa effective inpatients with central and periph-eral autonomic disorders. j Key words autonomic failure AEorthostatic hypotension AEDOPS AE droxidopa AEmultiple system atrophy AEpure autonomic failure AEParkinson’s disease AEnorepinephrine AE bloodpressure AE autonomic nervoussystem