title: Treatment of narcolepsy with L-tyrosine: double-blind placebo-controlled trial.
abstract: A randomised, double-blind, placebo-controlled study of L-tyrosine was done in ten subjects with narcolepsy and cataplexy. Of twenty-eight visual analogue scales rating mood and arousal, the subjects' ratings in the tyrosine treatment (9 g daily) and placebo periods differed significantly for only three (less tired, less drowsy, more alert). Ratings of daytime drowsiness, cataplexy, sleep paralysis, night-time sleep, overall clinical response, and measurements of multiple sleep latency and tests of speed and attention did not differ significantly between tyrosine and placebo periods. Dietary supplementation with tyrosine 9 g daily for 4 weeks seems to have a mild stimulant action on the central nervous system but this effect is not clinically significant in the treatment of the narcoleptic syndrome.
authors.affiliation: Department of Neurology, Institute of Psychiatry, King's College Hospital, London.
authors.forename: R D
authors.initials: RD
authors.lastname: Elwes
authors.forename: H
authors.initials: H
authors.lastname: Crewes
authors.forename: L P
authors.initials: LP
authors.lastname: Chesterman
authors.forename: B
authors.initials: B
authors.lastname: Summers
authors.forename: P
authors.initials: P
authors.lastname: Jenner
authors.forename: C D
authors.initials: CD
authors.lastname: Binnie
authors.forename: J D
authors.initials: JD
authors.lastname: Parkes
mesh_terms: D000328:Adult; D000339:Affect / Q000187:drug effects; D001143:Arousal / Q000187:drug effects; D001519:Behavior / Q000187:drug effects; D002385:Cataplexy / Q000188:drug therapy; D004311:Double-Blind Method; D004341:Drug Evaluation; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009290:Narcolepsy / Q000188:drug therapy*; D011897:Random Allocation; D012895:Sleep, REM / Q000187:drug effects; D014443:Tyrosine / Q000008:administration & dosage / Q000627:therapeutic use*
chemical_list: D014443:Tyrosine