Introduction: Melatonin is an endogenous hormone secreted to regulate circadian rhythms. While not FDA-approved, melatonin has been endorsed by multiple organizations as a first-line agent for insomnia. Patients in the intensive care unit (ICU) are particularly susceptible to disruptions in their sleep-wake cycle due to frequent stimuli, lab draws, and nursing care. In 2025, the Society of Critical Care Medicine made a new sleep recommendation, suggesting the use of melatonin in adult patients in the ICU. At this time, there is little guidance to support how to dose melatonin in critically ill patients. This study aims to characterize melatonin use at a large academic medical center. Methods: This single-center retrospective cohort study evaluates the use of melatonin for sleep in ICU patients at a large academic medical center. The primary outcome assessed the median starting dose and duration of melatonin use. Secondary outcomes evaluated if prescribers escalated melatonin doses, the use of adjunctive medications for sleep, utilization of a sleep-promotion protocol, and patient sedation and delirium scores. Outcomes were also compared between patients prescribed melatonin only versus those requiring adjunctive agents. Results: Among 97 patients, the median starting dose of melatonin was 6 mg, with a median duration of 11 days. While on melatonin, 13 patients received a dose increase to improve sleep, and 45% of patients used the sleep-promotion protocol. Across the cohort, 33 patients received adjunctive agents for sleep, with trazodone being the most used agent. Patients who required adjunctive sleep agents used higher doses of melatonin with a longer duration of therapy (median 16 vs. 8 days) but had lower utilization of the sleep promotion protocol (39% vs. 48%). There was no significant difference in nurse-reported sedation and delirium scores. Conclusions: While the optimal melatonin dose cannot be determined from this review alone, it revealed that patients often received an additional sleep agent instead of increasing or optimizing the melatonin dose. Future studies should explore dose escalations of melatonin monotherapy in conjunction with a sleep protocol while incorporating patient-reported quality of sleep.
Erdman et al. (Sun,) studied this question.