The overall purpose of this study is to identify a medication that might treat and/or prevent delirium in intensive care unit (ICU). Currently, there is no proven medical therapy for prevention or treatment of delirium. Ramelteon is a medication approved for insomnia. We hypothesize that ramelteon may help regulate the day/night cycle and decrease ICU delirium.

Melatonin is an endogenous hormone that regulates the sleep-wake cycle along with several other physiological functions. It is reported that melatonin secretion may be impaired in ICU patients, and there is some question whether this may be a contributing factor to delirium occurrence. Ramelteon is a melatonin agonist with three to six times increased affinity for MT1 and MT2 receptors versus melatonin. It is FDA approved for the treatment of insomnia, and some studies suggested some benefit with ramelteon for delirium prevention. There is limited prospective research data assessing the efficacy of ramelteon for delirium treatment. The goal of this study therefore is to assess the efficacy of ramelteon versus placebo on the prevention and treatment of delirium in ICU patients.

Inclusion Criteria:

• Medical or surgical ICU patient
• Ability to take oral or nasogastric tube within 48 hours of admission to ICU
• Expected ICU length of stay and life expectancy at least 48 hours
• Patient or POA capable of signing informed consent within 48 hours of ICU admission

Exclusion Criteria:

• Past medical history includes cirrhosis
• Active alcohol withdrawal
• Patients taking fluvoxamine prior to admission
• Self-reported hypersensitivity to ramelteon
• Incarcerated patients
• Pregnant patients
• Patients with acute neurological conditions including brain abscess, head bleed, meningitis
• Patients who are transferred from an outside hospital where they have resided for greater than 4 days
• Non-English speaking patients
• Hearing-impaired patients requiring sign language for communication
• Visually-impaired patients