There is very little evidence to guide the management of established delirium, and most existing trials were categorized by the investigators as pilot studies. Only one small placebo-controlled trial supports the efficacy of a drug treatment for established delirium in patients in the ICU. In a study of 36 patients who were randomly assigned to treatment with quetiapine or placebo, delirium resolved faster in patients who received quetiapine. The use of quetiapine also increased the number of patients who were discharged to their own home or to rehabilitation.52 A study of 103 patients who were randomly assigned to receive regular haloperidol, ziprasidone, or placebo showed no significant differences in the number of days that patients survived without delirium or coma.53 The single study comparing haloperidol with an atypical antipsychotic (olanzapine) showed equivalent efficacy.54 None of these trials distinguished between hyperactive and hypoactive delirium.