A commentary on the efficacy of olanzapine for the treatment of schizophrenia: the past, present, and future.

Olanzapine is a second-generation atypical antipsychotic with proven efficacy for the treatment of schizophrenia. Approved in 1996, olanzapine is one of the most studied antipsychotics, resulting in a considerable amount of clinical data across diverse patient populations. Despite the fact that olanzapine is associated with a known risk of metabolic side effects, including weight gain, many clinicians continue to prescribe olanzapine for the treatment of schizophrenia with the expectation of additional therapeutic antipsychotic efficacy relative to other first-line atypical antipsychotics. The goal of this narrative is to revisit the role of oral olanzapine in the management of patients with schizophrenia, including those with recently diagnosed schizophrenia ("first-episode"), those with an established schizophrenia diagnosis who experience acute exacerbations, those receiving long-term antipsychotic treatment as a maintenance intervention, and those with suboptimal response to antipsychotic treatment, including treatment resistance. Collectively, data from published literature support the favorable efficacy of olanzapine compared with other first- and second-generation antipsychotics, including lower rates of treatment discontinuation and clinically meaningful improvements in the symptoms of schizophrenia. The development of antipsychotic medications with the favorable efficacy of olanzapine, but with reduced weight gain, could address a major unmet need in the treatment of schizophrenia.