The serotonin reuptake inhibitors(SRIs) and the serotonin selective reuptake inhibitors(SSRIs) are considered the first choice agents for pharmacologic treatment of obsessive-compulsive disordr(OCD). However, many patients with OCD experience little or no improvement in their symptoms when treated with SRIs or SSRIs. Patients who have experienced a partial or no response to an SRI/SSRI at 10 to 12 weeks are often considered for augmentation strategies. Nearly every class of psychotropic medications has been tried in an open fashion, though augmentation strategies have been somewhat disappointing.