Sequential administration of augmentation strategies in treatment-resistant obsessive-compulsive disorder : preliminary findings

Given that an important proportion of patients with obsessive-compulsive disorder (OCD) fail to respond adequately to serotonin (5-HT) reuptake inhibitors (SRI), augmentation strategies aimed at enhancing further 5-HT transmission by different mechanisms were attempted sequentially in 13 SRI-resistant patients. Addition of the 5-HT 1A /1β-adrenergic antagonist pindolol did not alter OCD symptomatology but produced a rapid improvement of depressive symptoms. The 5-HT 1A agonist buspirone as well as 5-hydroxytryptophan, the immediate precursor of 5-HT, added to the SRI-pindolol regimen, were not effective in attenuating the intensity of OCD. Tryptophan, added to the SRI-pindolol regimen, produced a significant improvement after 4 weeks, with further amelioration after 6 weeks (36% decrease of the Yale-Brown Obsessive Compulsive Score), which was maintained with treatment prolongation.