[Is it valid to concurrently use multiple antipsychotics for patients with schizophrenia?]

The role of antipsychotic polypharmacy in the treatment of schizophrenia remains largely unknown, although such a mode of therapy has frequently been advocated on an empirical basis. This trend has especially been true in Japan. We briefly review current evidence in favor of and against polypharmacy in schizophrenia, then we show the data of revising antipsychotic polypharmacy to monotherapy. The study included 47 patients with chronic schizophrenia. Among the 44 patients assessable, 24 remained stable, 10 got better and 10 got worse after 24 weeks of maintenance monotherapy with the main agent. Overall, there were no significant differences in the Global Assessment of Functioning and the Global Impression of the participants. Conversion to antipsychotic monotherapy was feasible in 22 patients, while another 12 needed low dosages of low-potency agents. The chlorpromazine equivalent amount of antipsychotics was significantly reduced from 1,171 to 952 mg/day in 34 patients who were successful in switching. Although the procedure overall did not help patients much, it is suggested that many instances of antipsychotic polypharmacy are avoidable. Adding medications upon the emergence of symptoms might be an easy way to treat patients. Such an action should be validated in every case, however, and polypharmacy should be tested against prolonged, tenacious monotherapy.