A number of trials suggest that short-term use of atypical antipsychotics may be useful in the treatment of delirium associated with critical illness. However, long-term use of such agents for this indication has not been studied and may be associated with risks of adverse effects as well as unnecessary health care costs. A retrospective study of prescribing patterns of atypical antipsychotics initiated for the treatment of intensive care unit (ICU) delirium was performed to identify whether these agents were being discontinued prior to or upon hospital discharge. Of the 59 patients who met inclusion criteria and survived to hospital discharge, 28 (47%) were continued on the atypical antipsychotic upon discharge from the medical ICU. For those continued on the agent, 20 patients (71.4%) were prescribed continued therapy as an outpatient. Inpatient costs for atypical antipsychotics during the 9-month study period were increased by approximately $888. Annual cost of the medication as outpatient therapy is assessed at approximately $45,107. Although short-term trials of atypical antipsychotics may be useful for ICU delirium, caution is advised regarding potential adverse effects and added health care costs when use is prolonged.