A randomized controlled trial of D-cycloserine enhancement of exposure therapy for social anxiety disorder.
BACKGROUND
Pilot research has suggested that D-cycloserine (DCS) enhances treatment outcomes for anxiety disorders when employed as an adjunct to exposure therapy (ET). The aim of this study was to determine whether 50 mg of DCS enhances ET for social anxiety disorder (SAD) according to a comprehensive set of symptom and life impairment measures.


METHODS
In a randomized double-blind placebo-controlled trial, we administered 50 mg of DCS or placebo in combination with ET to 56 participants who met primary diagnosis for SAD.


RESULTS
Participants administered DCS reported greater improvement on measures of symptom severity, dysfunctional cognitions, and life-impairment from SAD in comparison with placebo-treated participants. Effect sizes were mostly in the medium range. Results also indicated that the amount of adaptive learning about one's ability to give speeches in front of an audience interacted with DCS to enhance treatment outcome.


CONCLUSIONS
This study shows that the administration of DCS before ET enhances treatment outcomes for SAD. Results also provide the first preliminary evidence to suggest that DCS moderates the relationship between a reduction in negative appraisals about one's speech performance and improvement in overall SAD symptoms.
Guastella
Adam J
AJ
School of Psychology, University of New South Wales, Sydney, Australia. a.guastella@unsw.edu.au
Richardson
Rick
R
Lovibond
Peter F
PF
Rapee
Ronald M
RM
Gaston
Jonathan E
JE
Mitchell
Philip
P
Dadds
Mark R
MR
D000293:Adolescent; D000328:Adult; D003131:Combined Modality Therapy; D003523:Cycloserine / Q000009:adverse effects / Q000627:therapeutic use*; D003887:Desensitization, Psychologic; D004311:Double-Blind Method; D005239:Fear / Q000187:drug effects / Q000528:radiation effects; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009517:New South Wales; D010698:Phobic Disorders / Q000175:diagnosis / Q000523:psychology / Q000628:therapy*; D011292:Premedication; D013060:Speech
D003523:Cycloserine