title: N-acetylcysteine add-on treatment in refractory obsessive-compulsive disorder: a randomized, double-blind, placebo-controlled trial.
abstract: OBJECTIVE
  This study aimed to evaluate the efficacy and safety of N-acetylcysteine, a glutamate-modulating agent, in patients with treatment-refractory obsessive-compulsive disorder as an adjunct to serotonin reuptake inhibitor treatment.
  
  
  METHODS
  Forty-eight patients (36 women; mean ± SD age, 30.93 ± 4.99) with obsessive-compulsive disorder who failed to respond to a course of serotonin reuptake inhibitor treatment were randomized to a 12-week intervention period of N-acetylcysteine (up to 2400 mg/d) or placebo. Primary outcome measures were the change in Yale-Brown Obsessive Compulsive Scale (Y-BOCS) score from baseline to end point and the rate of full response in each group at the end of trial. Full response was defined as 35% or greater reduction in Y-BOCS score from baseline.
  
  
  RESULTS
  Changes of Y-BOCS score were different over time (P < 0.001) and between groups (P < 0.001). N-acetylcysteine-assigned patients showed significantly improved mean Y-BOCS score (P = 0.003) and Clinical Global Impression-Severity of Illness scale score (P = 0.01) but not Clinical Global Impression-Improvement scale score at study end point. Of the patients in the N-acetylcysteine group, 52.6% were full responders at the end of the study, which was significantly higher than 15% of the patients in the placebo group (P = 0.013).
  
  
  CONCLUSIONS
  This trial suggests that N-acetylcysteine may be a safe and effective option to augment standard treatment in patients with refractory obsessive-compulsive disorder.
authors.affiliation: Isfahan Psychosomatic Research Center, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Hamid
authors.initials: H
authors.lastname: Afshar
authors.forename: Hamidreza
authors.initials: H
authors.lastname: Roohafza
authors.forename: Hamid
authors.initials: H
authors.lastname: Mohammad-Beigi
authors.forename: Mohammad
authors.initials: M
authors.lastname: Haghighi
authors.forename: Leila
authors.initials: L
authors.lastname: Jahangard
authors.forename: Pedram
authors.initials: P
authors.lastname: Shokouh
authors.forename: Masoumeh
authors.initials: M
authors.lastname: Sadeghi
authors.forename: Hasan
authors.initials: H
authors.lastname: Hafezian
mesh_terms: D000111:Acetylcysteine / Q000008:administration & dosage*; D000328:Adult; D004311:Double-Blind Method; D004359:Drug Therapy, Combination; D005260:Female; D006801:Humans; D008297:Male; D009771:Obsessive-Compulsive Disorder / Q000188:drug therapy* / Q000453:epidemiology / Q000523:psychology*; D017367:Selective Serotonin Reuptake Inhibitors / Q000008:administration & dosage*; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D000111:Acetylcysteine; D017367:Selective Serotonin Reuptake Inhibitors