Marked improvement in delirium with ramelteon: five case reports.

Delirium is a common and serious acute neuropsychiatric syndrome characterized by inattention and global cognitive dysfunction. Delirium is associated with higher morbidity, higher mortality and longer hospitalization, but its aetiology remains unclear. We successfully treated five cases of delirium within 1 day with ramelteon, a novel selective melatonin receptor agonist. This suggests that correction of the circadian rhythm disturbance, one of the main symptoms of delirium, plays a crucial role in its treatment and sheds new light on a therapeutic strategy for treatment of delirium.