The pharmacotherapy of obsessive-compulsive disorder.

Potent inhibitors of 5-hydroxytryptamine (5-HT) reuptake have clearly been established as the first-line pharmacotherapy for treatment of obsessive-compulsive disorder (OCD). Although a variety of tricyclic antidepressants and monoamine oxidase inhibitors have similar efficacy in the treatment of depression and panic disorder, potent blockade of 5-HT transport appears to be a prerequisite for effective treatment of OCD. Adding agents that enhance 5-HT neurotransmission to ongoing treatment in patients whose OCD is refractory to 5-HT reuptake inhibitors has not yielded impressive results. However, the addition of low-dose dopamine (DA) antagonists to the regimens of treatment-resistant patients appears to be a potentially useful strategy for the specific subgroup of OCD patients with a comorbid chronic tic disorder such as Tourette's syndrome. Because of the toxicity associated with neuroleptics, a time-limited trial of those agents, with reassessment at regular intervals, is indicated. Pharmacologic studies suggest that both the 5-HT and DA systems may be critical to the treatment and possibly the pathophysiology of OCD.