N-acetylcysteine augmentation therapy for moderate-to-severe obsessive-compulsive disorder: randomized, double-blind, placebo-controlled trial

What is known and objectiveN-acetylcysteine (NAC) has been proposed as a potential therapy for obsessive-compulsive disorder (OCD) as it may regulate the exchange of glutamate and prevent its pre-oxidant effects. The aim of the present double-blind, placebo-controlled trial was to assess the efficacy and tolerability of NAC augmentation in moderate-to-severe (OCD) treatment. MethodsIn this randomized, double-blind, two-centre, placebo-controlled, 10-week trial, patients with moderate-to-severe OCD were enrolled. Patients were randomized into two parallel groups to receive fluvoxamine (200 mg daily) plus placebo or fluvoxamine (200 mg daily) plus NAC (2000 mg daily). A total of 44 patients (22 in each group) were visited to evaluate response to therapy using the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) at baseline, and at weeks 4, 8 and 10. Side effects were recorded using predesigned checklists upon each visit. Results and discussionRepeated-measures ANOVA showed a significant effect for time x treatment interaction (Greenhouse-Geisser corrected: F = 514, d.f. = 164, P = 0012) in the Y-BOCS total score and a significant effect for time x treatment interaction (Greenhouse-Geisser corrected: F = 544, d.f. = 154, P = 0011) in the Y-BOCS obsession subscale between the two groups. What is new and conclusionOur results showed that NAC might be effective as an augmentative agent in the treatment of moderate-to-severe OCD. Trial registrationIranian Registry of Clinical Trials (): IRCT201405271556N60