Randomized controlled trial of add-on Fluoxetine versus usual antipsychotic treatment in obsessive compulsive symptoms in schizophrenia.

BACKGROUND

Schizophrenia can coexist with obsessive-compulsive symptoms (OCSs). This study aimed to assess the efficacy of adding Fluoxetine-gold standard for the treatment of obsessive-compulsive disorder to the treatment regimen of patients with schizophrenia and OCS.

METHODS

Patients diagnosed with schizophrenia (according to ICD-11) and OCS (assessed via the Y-BOCS Checklist) were randomized to either the Add-on Fluoxetine (received Fluoxetine in addition to their ongoing antipsychotic treatment) or the Antipsychotic only (continued with standard therapy) using a computer-generated random number table and assessed using PANSS, CGI-global impression, and SOFAS. Baseline assessments were conducted to evaluate sociodemographic and clinical factors and the severity of OCS. Both groups were monitored over 8 weeks for changes in psychotic and obsessive-compulsive symptoms.

RESULTS

Seventy patients of schizophrenia with OCS were recruited, 35 in each group. Both groups demonstrated significant improvement over 8 weeks in psychotic and obsessive-compulsive symptoms. The Add-on Fluoxetine exhibited earlier and more pronounced symptom improvements. A significant difference was found in the YBOCS compulsion score, with a median score of 8 (7-10) in the Add-on Fluoxetine and 11 (9.5-12) in the Antipsychotic only ( value of 0.003). Add-on Fluoxetine had a lower median score on CGI global improvement, 3 (3-3), and CGI efficacy index, 10 (10-10), than the Antipsychotic only, 4 (3-4) and 14 (10-14), respectively ( value < 0.001). Fluoxetine was well tolerated, with minimal reported side effects.

CONCLUSIONS

The findings suggest that adjunctive Fluoxetine treatment led to early resolution of psychopathology and improved overall outcomes in schizophrenia with co-occurring OCS.