Obsessive-Compulsive Disorder

Abstract

Obsessions, compulsions and rituals have been recognised as abnormal cognitions and behaviours for several centuries. These symptoms and signs, which have been variously referred to in different ages and cultures, are encompassed under the present diagnosis of obsessive-compulsive disorder (OCD). OCD has been an elusive nosological entity, resistant to treatment until the last 30 years. In 1966, two distinct treatment modalities, a potent serotonin (5-hydroxytryptamine; 5-HT) reuptake inhibitor (SRI) and behavioural therapy, were introduced. Today, SRIs and behavioural therapy remain important interventions in modern OCD management, underscoring the fact that more effective modes of treatment have not been developed. Despite recent advances in understanding the underlying neurobiology of OCD, its treatment remains a challenge. At present, the mainstay of treatment is a combination of pharmacotherapy and behavioural therapy. In terms of pharmacotherapy, the most effective class of medication remains the SRIs. Clomipramine and the selective SRIs fluoxetine, fluvoxamine, paroxetine and sertraline have all demonstrated efficacy and are regarded as first-line agents for monotherapy. If multiple trials of SRIs do not result in improvement, alternative monotherapy may be attempted with monoamine oxidase inhibitors, buspirone or clonazepam. If monotherapy achieves partial response, augmentation of SRIs or combinations of agents may be considered. Only haloperidol has demonstrated efficacy as an augmentation of an SRI in a controlled trial and only in patients with comorbid tic disorders. There is support from noncontrolled trials for some other augmenting agents. Of the psychotherapeutic techniques, only behavioural therapy in the form of exposure and response prevention (ERP) has demonstrated significant effectiveness. Optimal results in the management of OCD are often realised through a combination of ERP and pharmacological therapy, although the availability of behavioural therapy is limited. For the small proportion of patients who are severely disabled by prolonged treatment-resistant OCD, neurosurgery may be an effective treatment option.