Introduction: The addition of typical and atypical antipsychotics in patients with obsessive-compulsive disorder (OCD) resistant to serotonin reuptake inhibitors (SRI) has been reported as a useful augmentation strategy. Although antipsychotic monotherapy has been associated with ineffectiveness and even increase of psychotic symptoms (especially in psychotic patients), antipsychotics as concomitant medications have proven to be effective in several case series and pilot clinical trials. The objective of this case series was to evaluate effectiveness of risperidone as add on therapy to current SRIs treatment in OCD refractory to treatment patients.
Material and method: Risperidone add on therapy in moderate and severe treatment resistant OCD patients was reviewed. Case reports were patients fulfilling the following criteria: a) treatment follow-up of at least 12 weeks; b) SRI adequate doses, y c) Y-BOCS score higher than 16 score before starting treatment. A three month follow-up period was reviewed. Risperidone starting dose was low (mean 1.5 mg/day) and was increased following clinical criteria. Therapeutic response and tolerability were evalated with the following scales: Y-BOCS, CGI of change, UKU (neurological subscale) and spontaneous reported adverse events. Response criteria were the following: at least 35% of reduction in Y-BOCS from basal score and final score less than 16 and CGI-C "much improved" or "very much improved" (score 1 or 2). Intention to treat analysis was performed (patients who reported at least one risperidone dose and effectiveness measure).
Results: 31 patients had at least one effectiveness evaluation and 21/31 patients (67.8 %) were considered treatment responders. Mean risperidone dose was 3.8 mg/day. In general, risperidone was well tolerated: serious or unexpected adverse event were not reported.
Conclusion: Risperidone as add on therapy to SRI in moderate-severe, refractory to treatment OCD patients, may be an effective and safe strategy.