Introduction: 40%-60% of the patients with obsessive-compulsive disorder (OCD) remain unimproved by Serotonin-Reuptake inhibitors. The objective of this study was to examine whether addition of the atypical antipsychotic olanzapine to SRIs is useful for patients with OCD who do not respond to SRI monotherapy.
Method: eleven patients with OCD (DSM IV-TR criteria) who had not respond to at least one SRI at maximum dose and duration were assigned to receive olanzapine in addition to their SRIs for 8 weeks. Treatment response was assessed using the Yale-Brown Obsessive-Compulsive Scale (YBOCS).
Results: six of 11 patients respond to the olanzapine addition. The mean+/-SD baseline YBOCS score of 33.45 +/- 4.47 dropped to a mean of 25 +/- 5.98 at endpoint with a mean reduction of 24.56%.
Conclusion: This is the first study in Iran to show that treatment-refractory OCD Patients may benefit from addition of olanzapine to ongoing SRI therapy.