Subcutaneous Olanzapine for Hyperactive or Mixed Delirium in Patients with Advanced Cancer: A Preliminary Study

Abstract Context Oral olanzapine is effective in controlling agitation in patients with delirium, but often, parenteral administration is necessary. Intramuscular (IM) olanzapine is approved for managing agitation in schizophrenia, but this route is inappropriate for terminally ill patients. Objectives The purpose of this pilot study was to determine the safety and tolerability of subcutaneous (SC) olanzapine in the management of hyperactive or mixed delirium in patients with advanced cancer. Methods We conducted a prospective open-label study in patients with advanced cancer who had agitated delirium (Richmond Agitation Sedation Scale [RASS] score ≥+1) that had not responded to a 10 mg or higher dose of parenteral haloperidol over 24 hours. Patients received olanzapine 5 mg SC every eight hours for three days and continued haloperidol for breakthrough agitation. For patients requiring more than 8 mg of rescue haloperidol daily, the olanzapine dose was increased to 10 mg SC every eight hours. Injection site, systemic toxicity, and efficacy (RASS score