Interventions to reduce antipsychotic polypharmacy: A systematic review

Background: It still remains unclear as to how to counteract antipsychotic polypharmacy that remains controversial but common. The objective of this study was to synthesize the clinical evidence to reduce antipsychotic polypharmacy (i.e. use of multiple antipsychotics) in schizophrenia. Methods: A literature search was performed to identify clinical trials that attempted to reduce antipsychotic polypharmacy in patients with schizophrenia by any form of systematic intervention using PubMed as well as MEDLINE, EMBASE, and PsycINFO (last search: June 2012). The search terms included "antipsychotics" and "polypharmacy". Cross-referencing was also performed. Results: The literature search identified 17 studies. Only 3 studies (1 randomized controlled trial and 2 open-label trials) were found that systematically switched antipsychotic polypharmacy to monotherapy. In two of them, more than two thirds of the subjects successfully completed the switch (40/58, 69.0%; 34/44, and 77.3%, respectively) while less than half the subjects tolerated it in the other study (6/14 and 42.9%) although the sample size was very small. On the other hand, 14 studies that examined impacts of interventions have physicians refrain from antipsychotic polypharmacy. While a modest intervention with educational approach alone was effective in three of the five articles, a more assertive intervention that directly cautioned physicians on the use of polypharmacy was effective in 10 of 12 articles. Conclusion: The literature search revealed the paucity of the data. Careful switching from polypharmacy to monotherapy seems feasible in a majority of patients with schizophrenia. Assertive interventions, rather than passive educational approaches alone, appear more effective in reducing antipsychotic polypharmacy.