Post-clozapine in a clinical setting: A retrospective case note review in Kumamoto, Japan (2009-2019)

Clozapine is commonly prescribed in dopamine supersensitivity psychosis (DSP) cases in Japan. However, limited knowledge on treatment post-clozapine discontinuation use exists. We investigated antipsychotic medications, patient status, and DSP episodes before, during, and after clozapine treatment using medical records of 30 schizophrenia patients (mean age, 51 years; mean illness duration before clozapine treatment, 24 years; mean clozapine treatment duration, 1.6 years), who discontinued clozapine between 2009 and 2019. In our region, long-acting injectable antipsychotic monotherapy and polypharmacy (half with aripiprazole) accounted for 17% and 50% post-clozapine use, respectively. Furthermore, patient status rarely improved with subsequent DSP treatment, including clozapine re-initiation.