Augmentation of clozapine with another pharmacological agent: treatment for refractory schizophrenia in the ‘real world’

Abstract

Refractory schizophrenia (SZ) affects approximately 30% of people with SZ. Clozapine (CLZ) is the gold standard treatment; however, there are still patients who are non-responsive or partially responsive to treatment. Although a lack of evidence exists in reality, these patients are treated with a combination of agents in addition to CLZ. Therefore, this article reviews the prevalence of the augmentation of CLZ with additional agents. This study was cross-sectional; physicians in a region of Australia in May 2011 were contacted to provide details of their patients on CLZ and any additional agents. The data set consists of 84 patients. The majority of the patients 84.5% were taking at least one additional agent. Of those taking additional agents, they derived from the following classes' antipsychotics (72%), antidepressants (30%), mood stabilisers (17%), antimetabolic agents (13%), benzodiazepines (7%), anticholinergics (4%) and miscellaneous agents (12.5%). It is apparent that CLZ is routinely augmented with other agents despite the lack of an evidence base. However, concerning was the lack of augmentation with antimetabolic agents despite the paucity of literature reporting the detrimental impact of antipsychotic treatment upon patients metabolic indices. The findings are discussed in the context of the current recommendations and empirical literature.