Melatonin: A Review of the Evidence for Use in Hospital Settings.

New onset insomnia is often experienced by patients during hospitalization due to environmental disruptions, pain and increased patient care activities. Patient distress arising from poor sleep quality and quantity often results in the prescribing of hypnotics. Melatonin use in hospital settings is common and is increasingly used for off label indications including primary insomnia in those aged < 55 years, prevention of delirium and to facilitate benzodiazepine discontinuation. A literature review was conducted to evaluate the efficacy, effectiveness, safety, tolerability, and cost-effectiveness of melatonin for various off-label indications in inpatient hospital settings. The review found limited high quality evidence demonstrating a clinically meaningful benefit from melatonin in improving sleep, delirium, or facilitating benzodiazepine discontinuation in the inpatient setting. Study findings were inconsistent, and those that did show statistical improvement were of uncertain clinical benefit. The review also found a paucity of data on the safety of melatonin when used in hospitalized patients, and no evidence to support cost-effectiveness. Non-pharmacological interventions are recommended as first-line treatment of insomnia and for the prevention of delirium in inpatient settings. The use of interventions without evidence for efficacy or effectiveness is contrary to the quality use of medicines principles in Australia's National Medicines Policy. Context-specific evidence on the efficacy and effectiveness of a medicine should guide clinician decision-making and prescribing, to improve the quality use of medicines.