Pharmacological treatment for obsessive–compulsive disorder

The systematic investigation of obsessive–compulsive disorder (OCD) has depended on the introduction of universally accepted diagnostic criteria and comprehensive rating scales that are sensitive enough to measure small treatment-related changes, such as the Yale–Brown Obsessive Compulsive Scale. This contribution reviews the key clinical questions relating to pharmacotherapy for OCD. After 30 years of intensive pharmacological investigation, it still appears to be the case that OCD responds selectively to drugs that act as powerful inhibitors of the synaptic reuptake of serotonin – clomipramine and the selective serotonin reuptake inhibitors (SSRIs). Drugs lacking potent serotonin reuptake inhibitor (SRI) actions, such as the tricyclic antidepressants amitriptyline, nortyiptyline and desipramine, and the monoamine oxidase inhibitors (MAOIs) clorgyline and phenelzine, have not been found to be effective in controlled studies. Nor is there convincing evidence supporting the efficacy of benzodiazepines, lithium or electroconvulsive therapy (ECT). However, symptoms often respond only partially to SRIs and for around one-third of cases the response is poor. Increasing dosages or switching between SRIs are practical next steps. Growing evidence supports the efficacy of adding first- or second-generation antipsychotic agents, but long-term data are lacking.