Paroxetine versus Clomipramine in the Treatment of Obsessive–Compulsive Disorder

BACKGROUND: The aim was to assess the effect of a flexible dose of paroxetine, compared with clomipramine and placebo, in obsessive-compulsive disorder (OCD). METHOD: In a multinational randomised study, 406 subjects with OCD of at least six months duration received double-blind medication for up to 12 weeks. Doses were adjusted according to therapeutic effect and side-effects. Primary efficacy measures were the Yale-Brown Obsessive-Compulsive Scale and the National Institute of Mental Health Obsessive-Compulsive Scale. Secondary efficacy measures were the Montgomery-Asberg Depression Rating Scale, Symptom Check-List (90), Clinical Global Impression, and Patients Global Evaluation. RESULTS: Paroxetine was significantly more effective than placebo, and of comparable efficacy to clomipramine. Paroxetine had significantly superior tolerability to clomipramine on three measures: CGI efficacy index, anticholinergic adverse events, and adverse events leading to withdrawal. CONCLUSION: Paroxetine is as effective as clomipramine in the treatment of OCD. The comparable efficacy and better tolerability of paroxetine suggest that it would be an appropriate treatment for OCD.