This study is a retrospective, multi-center, observational study. Based on the Institutional Review Board (IRB) approval date, patients will be registered who had been stably taking atypical antipsychotics (Aripiprazole, Olanzapine, Quetiapine) for more than 8 weeks during the past period for the treatment of bipolar disorder, but changed the medication to Lurasidone due to metabolic side effects (weight gain) (patients followed up for 16 weeks). Clinical effectiveness and safety information, such as adverse events, will be collected through body weight and questionnaires (HAM-D, CGI-S, CGI-I) before and after switching Lurasidone.
