Medication sleuth: an important role for pharmacists in determining the etiology of delirium.

Delirium is characterized by disturbances of consciousness, attention, cognition, and perception and is the most common reason for acute cognitive dysfunction in hospitalized elderly patients. Causes of delirium can be multifactorial, and a careful medical and medication history can help determine the underlying cause of behavioral disturbances. A 65-year-old patient with a history of chronic pain, insomnia, and multiple medical problems, who presented with altered mental status and aggressive behavior, is described. The patient had taken an overdose of zolpidem prior to admission, and she required chemical and physical restraints and one-on-one care for safety. With time and washout of the zolpidem, the patient's behavior did not improve. On the second day of admission, medication reconciliation of this patient's medication profile helped to reveal a medication cause for this patient's delirium. A pharmacist should be included early in the process of obtaining a medication history. Recommendations for the management of chronic pain and insomnia in the elderly are presented.