title: Lamotrigine Augmentation Versus Placebo in Serotonin Reuptake Inhibitors-Resistant Obsessive-Compulsive Disorder: A Randomized Controlled Trial.
abstract: OBJECTIVE
  Serotonin reuptake inhibitors are frequently used in first-line treatments for patients with obsessive-compulsive disorder. Nevertheless, many of these patients do not respond well to initial therapy. The hypothesis of glutamatergic dysfunction in specific brain regions has been proposed in the pathophysiology of obsessive-compulsive disorder. This study was designed to evaluate the possible efficacy of lamotrigine, a glutamatergic agent in Serotonin reuptake inhibitors-resistant patients with obsessive-compulsive disorder.
  
  
  METHODS
  This study was a 12-week, double blind, randomized, placebo-controlled trial of adjunctive fixed-doses of lamotrigine (100 mg) to Serotonin reuptake inhibitors therapy in obsessive-compulsive disorder. Eligible subjects who had a total Y-BOCS of 21 or above were randomly assigned to receive adjunctive treatment with either lamotrigine (n = 26), or placebo (n = 27). Response to lamotrigine was defined as clinical improvement (>25% decrease in the total Y-BOCS score), which was administered at weeks 0, 8 and 12.
  
  
  RESULTS
  At the endpoint (week 12), significant differences were observed in obsession, compulsion, and total Y-BOCS scores comparing lamotrigine to placebo (P = 0.01, 0.005 and 0.007 respectively). The mean reduction in obsession, compulsion and total scores in lamotrigine group was about 4.15, 4.50 and 8.73, respectively. Similarly, the mean reductions in the placebo group were 2.52, 2.56 and 5.07. Effect sizes for efficacy measureswerecalculatedbyCohen'sd, and it was calculated as 0.54 for the total YBOCS.
  
  
  CONCLUSIONS
  Our findings provide evidence that this augmentation is well tolerated and may be an effective strategy for patients with refractory obsessive-compulsive disorder.
authors.affiliation: Department of Psychiatry, Guilan University of Medical Sciences, Rasht, Iran. Email: khalkhali@gums.ac.ir.
authors.forename: Mohammadrasoul
authors.initials: M
authors.lastname: Khalkhali
authors.affiliation: Department of Psychiatry, Guilan University of Medical Sciences, Rasht, Iran. Email: setareh.aram@gums.ac.ir.
authors.forename: Setareh
authors.initials: S
authors.lastname: Aram
authors.affiliation: Department of Psychiatry, Guilan University of Medical Sciences, Rasht, Iran. Email: zarrabi@gums.ac.ir.
authors.forename: Homa
authors.initials: H
authors.lastname: Zarrabi
authors.affiliation: Department of Psychology, Guilan University, Rasht, Iran. Email: mosakafie@yahoo.com.
authors.forename: Moosa
authors.initials: M
authors.lastname: Kafie
authors.affiliation: Department of Community Medicine, Guilan University of Medical Sciences, Rasht, Iran. Email: Heidarzadeh@gums.ac.ir.
authors.forename: Abtin
authors.initials: A
authors.lastname: Heidarzadeh
keywords: Drug Augmentation; Lamotrigine; Obsessive-Compulsive Disorder; Serotonin Reuptake Inhibitors; Treatment-Resistant