Common second-generation antipsychotic medications are causing symptoms of obsessive-compulsive disorder to emerge in many people who previously only had schizophrenia symptoms, according to a review of the medical literature published in Current Psychiatry Reports. In some cases, the researchers wrote, these symptoms are occurring for the first time, or significantly worsening, in nearly half of patients, or causing “full threshold Obsessive Compulsive Disorder.”
Researchers from the Toronto Centre for Addiction and Mental Health and University of Toronto reviewed experimentally-designed, peer-reviewed articles published in English from 1960 to 2014. They found, “evidence of the role of both olanzapine and, more robustly, clozapine in the induction and worsening of OCS [obsessive compulsive symptoms] in schizophrenia.”
“Our findings suggest that clozapine confers the greatest risk of OCS in schizophrenia, with 20 to 28% of clozapine-treated patients experiencing de novo OCS, in addition to 10 to 18% incurring an exacerbation of pre-existing OCS,” concluded the researchers. “Clozapine can also yield full threshold obsessive-compulsive disorder (OCD), in some cases. Olanzapine is another high risk drug for secondary OCS which occurs in 11 to 20% of schizophrenic patients receiving olanzapine therapy.”
The researchers did not find enough research evidence to characterize the effects of other second-generation antipsychotics.
(Abstract) Second Generation Antipsychotic-Induced Obsessive-Compulsive Symptoms in Schizophrenia: A Review of the Experimental Literature (Fonseka, Trehani M. et al. Current Psychiatry Reports. September 2014, 16:510. DOI: 10.1007/s11920-014-0510-8)