A controlled trial of levodopa plus carbidopa in the treatment of winter seasonal affective disorder: a test of the dopamine hypothesis.
The objectives of this study were to test the hypothesis that a dopaminergic deficiency plays a role in the pathogenesis of winter seasonal affective disorder (SAD) and to test the efficacy of levodopa plus carbidopa as a treatment for SAD. Two weeks of double-blind placebo washout were followed by random assignment to parallel treatments for 2 weeks with levodopa and carbidopa versus placebo. Observations were made during weekly outpatient visits. All subjects met criteria for SAD. Fifty patients entered the study. Twenty-four were significantly depressed after the washout period and were randomly assigned to medication or placebo. Twenty-three completed the study. Twelve patients received placebo capsules four times a day during the 2-week drug comparison period. On an identical schedule, 11 patients received capsules containing levodopa (up to 7 mg/kg per day by the end of the second week) and carbidopa (100 mg/day). Twenty-one item Hamilton Rating Scale for Depression scores were used to determine antidepressant efficacy. No differences were found in the rates of response. There is no evidence to support the use of levodopa for the treatment of SAD patients in general. A model of systemic dopaminergic deficiency does not readily explain the pathology of SAD.
Oren
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DA
Section on Environmental Psychiatry, National Institute of Mental Health, Bethesda, Maryland 20892.
Moul
D E
DE
Schwartz
P J
PJ
Wehr
T A
TA
Rosenthal
N E
NE
D000328:Adult; D002230:Carbidopa / Q000008:administration & dosage / Q000627:therapeutic use*; D004298:Dopamine / Q000502:physiology; D004311:Double-Blind Method; D004334:Drug Administration Schedule; D004359:Drug Therapy, Combination; D005260:Female; D006801:Humans; D007980:Levodopa / Q000008:administration & dosage / Q000627:therapeutic use*; D008297:Male; D011581:Psychological Tests; D016574:Seasonal Affective Disorder / Q000175:diagnosis / Q000188:drug therapy* / Q000209:etiology
D007980:Levodopa; D002230:Carbidopa; D004298:Dopamine