title: Does D-cycloserine enhance exposure therapy for anxiety disorders in humans? A meta-analysis.
abstract: The treatment of anxiety is on the edge of a new era of combinations of pharmacologic and psychosocial interventions. A new wave of translational research has focused on the use of pharmacological agents as psychotherapy adjuvants using neurobiological insights into the mechanism of the action of certain psychological treatments such as exposure therapy. Recently, d-cycloserine (DCS) an antibiotic used to treat tuberculosis has been applied to enhance exposure-based treatment for anxiety and has proved to be a promising, but as yet unproven intervention. The present study aimed to evaluate the efficacy of DCS in the enhancement of exposure therapy in anxiety disorders. A systematic review/meta-analysis was conducted. Electronic searches were conducted in the databases ISI-Web of Science, Pubmed and PsycINFO. We included only randomized, double-blind, placebo-controlled trials with humans, focusing on the role of DCS in enhancing the action of exposure therapy for anxiety disorders. We identified 328 references, 13 studies were included in our final sample: 4 on obsessive-compulsive disorder, 2 on panic disorder, 2 on social anxiety disorder, 2 on posttraumatic stress disorder, one on acrophobia, and 2 on snake phobia. The results of the present meta-analysis show that DCS enhances exposure therapy in the treatment of anxiety disorders (Cohen d =  -0.34; CI: -0.54 to -0.14), facilitating the specific process of extinction of fear. DCS seems to be effective when administered at a time close to the exposure therapy, at low doses and a limited number of times. DCS emerges as a potential new therapeutic approach for patients with refractory anxiety disorders that are unresponsive to the conventional treatments available. When administered correctly, DCS is a promising strategy for augmentation of CBT and could reduce health care costs, drop-out rates and bring faster relief to patients.
authors.affiliation: Institute of Psychiatry, Universidade Federal do Rio de Janeiro (IPUB-UFRJ), Rio de Janeiro, Brazil.
authors.forename: Helga
authors.initials: H
authors.lastname: Rodrigues
authors.affiliation: Institute of Psychiatry, Universidade Federal do Rio de Janeiro (IPUB-UFRJ), Rio de Janeiro, Brazil.
authors.forename: Ivan
authors.initials: I
authors.lastname: Figueira
authors.affiliation: Institute of Psychiatry, Universidade Federal do Rio de Janeiro (IPUB-UFRJ), Rio de Janeiro, Brazil.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Lopes
authors.affiliation: Institute of Psychiatry, Universidade Federal do Rio de Janeiro (IPUB-UFRJ), Rio de Janeiro, Brazil.
authors.forename: Raquel
authors.initials: R
authors.lastname: Gonçalves
authors.affiliation: Department of Psychiatry and Mental Health, Universidade Federal Fluminense (MSM-UFF), Niteroi, Brazil.
authors.forename: Mauro Vitor
authors.initials: MV
authors.lastname: Mendlowicz
authors.affiliation: Department of Epidemiology, Escola Nacional de Saúde Pública (ENSP-FIOCRUZ) Rio de Janeiro, Brazil.
authors.forename: Evandro Silva Freire
authors.initials: ES
authors.lastname: Coutinho
authors.affiliation: Institute of Psychology, Universidade Federal do Rio de Janeiro (IPUB-UFRJ), Rio de Janeiro, Brazil.
authors.forename: Paula
authors.initials: P
authors.lastname: Ventura
mesh_terms: D000963:Antimetabolites / Q000627:therapeutic use*; D001008:Anxiety Disorders / Q000188:drug therapy* / Q000503:physiopathology; D003523:Cycloserine / Q000627:therapeutic use*; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008297:Male; D039781:PubMed; D016032:Randomized Controlled Trials as Topic
chemical_list: D000963:Antimetabolites; D003523:Cycloserine