Most acute psychotic episodes are regarded as indicators of schizophrenia. We developed an algorithm for the treatment of such episodes. In Japan, psychiatrists tend to prescribe two or more neuroleptics at once, but it is thought that using a single neuroleptic is better, and the algorithm we report is based on this view. Since there are few reports on how to choose and use a single neuroleptic in Japan, our method is simply an example, with insufficient scientific support. It will need to be revised in future.