‎ Lamotrigine Augmentation versus Placebo in Serotonin ‎Reuptake Inhibitors-‎Resistant Obsessive-Compulsive Disorder: ‎A Randomized Controlled Trial

• Main Authors: Mohammadrasoul Khalkhali, Setareh Aram‎, Homa Zarrabi, Moosa Kafie, Abtin Heidarzadeh
• Format: Article
• Language: English
• Published: Tehran University of Medical Sciences 2016-06-01
• Series: Iranian Journal of Psychiatry
• Subjects: Drug Augmentation; Lamotrigine; ‎Obsessive-Compulsive Disorder; ‎Serotonin Reuptake ‎Inhibitors; ‎Treatment-Resistant
• Online Access: https://ijps.tums.ac.ir/index.php/ijps/article/view/709

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.‎ Method: 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 ‎measures were calculated by Cohen’s d, and it was calculated as 0.54 for the total ‎YBOCS.‎ Conclusion: Our findings provide evidence that this augmentation is well tolerated and may be an ‎effective strategy for patients with refractory obsessive-compulsive disorder.‎‎