Olanzapine addition in obsessive-compulsive disorder refractory to selective serotonin reuptake inhibitors: An open-label case series

Background: Despite the efficacy of selective serotonin reuptake inhibitors (SSRIs) in the treatment of obsessive-compulsive disorder, a significant n umber of patients show no or only partial remission of symptoms. Some evide nce exists to suggest that risperidone augmentation can be helpful in treat ing this refractory group. The efficacy of other atypical antipsychotic age nts, such as olanzapine, in augmenting SSRIs in refractory obsessive-compul sive patients has yet to be systematically investigated. Method: A series of 10 patients with DSM-IV obsessive-compulsive disorder s howing significant residual symptoms following an adequate SSRI trial (12 w eeks) were given open-label olanzapine augmentation for a minimum of an add itional 8 weeks. Treatment response was assessed using the Yale-Brown Obses sive Compulsive Scale and the Clinical Global Impressions scale. Results: Nine of the 10 patients in this series treated with olanzapine and an SSRI completed the 8-week augmentation trial, Of these, 4 demonstrated a complete remission or major improvement in obsessive-compulsive symptoms, 3 had partial remission, and 2 experienced no benefit. Nine patients exper ienced minimal adverse effects, primarily sedation, which did not interfere with continuing treatment. One patient discontinued olanzapine owing to ex cessive sedation. Conclusion: The results of this preliminary, open-label trial suggest that olanzapine may be effective in augmenting ongoing SSRI treatment for a port ion of patients with obsessive-compulsive disorder refractory to SSRI treat ment. Larger, placebo-controlled trials appear warranted to investigate the clinical efficacy and tolerability of olanzapine augmentation of SSRI trea tment in SSRI-refractory obsessive-compulsive disorder.