Abstract
Delirium is an acute decline of consciousness and cognition that historically has been treated with haloperidol. Because of its side effect profile, there has been a recent increase in the use of atypical antipsychotics for this indication. Objective: To systematically evaluate the literature about the use of olanzapine in the treatment of delirium using the analysis of Evidence-Based Medicine. Design: The first step was the identification of a problem, followed by the definition of a structured question, the sistematic search of the existing studies and finally the objective analysis of the validity of the results. Results: Following a search in Medline, five studies that address the issue were identified. All of them have major methodological shortcomings and in some cases there are important ethical concerns. Conclusions: First, olanzapine has a level 3 of clinical evidence for its use as a treatment for delirium. Second, a methodological improvement in the structure of these studies is urgently required, acompanied by the strict application of the ethical principles of research. Third, the DRS is a widely used scale to quantify the severity of delirium. Forth, a critical review of the literature is essencial to assess the scientific evidence.