Duloxetine Augmentation in Resistant Obsessive-Compulsive Disorder: A Double-Blind Controlled Clinical Trial

The aim of this study is to evaluate the efficacy of duloxetine augmentation in treatment of resistant obsessive-compulsive disorder (OCD).

This augmentation trial was designed as an 8-week randomized controlled, double-blind study. Forty-six patients experiencing OCD who had failed to respond to at least 12 weeks of treatment with a selective serotonin reuptake inhibitor (fluoxetine, citalopram, or fluvoxamine) were randomly allocated to receive duloxetine or sertraline plus their current anti-OCD treatment. The Yale-Brown Obsessive Compulsive Scale (Y-BOCS) was the primary outcome measure. Treatment response was defined as 25% or more decrease in scores of Y-BOCS. The mean dosage of duloxetine was 44.4 mg/d (range, 20-60 mg/d), and the mean dosage of sertraline was 123.8 mg/d (range, 50-200 mg/d).

Forty-six patients (24 of 30 in duloxetine group and 22 of 27 in sertraline group) completed the trial. Both groups showed improvement during the 8-week study period (mean Y-BOCS total score at week 8 as compared with baseline: P < 0.001 & P < 0.001) without significant difference (P = 0.861). Those receiving duloxetine plus their initial medications experienced a mean decrease of 33.0% in Y-BOCS score, and the patients with sertraline added to their initial medication experienced a mean decrease of 34.5% in Y-BOCS.

Our double-blind controlled clinical trial showed duloxetine to be as effective as sertraline in reducing obsessive and compulsive symptoms in patients with resistant OCD. However, it needs to be noted that our study is preliminary, and larger double-blind placebo-controlled studies are necessary to confirm the results.