Melatonin

Melatonin is a neurohormone synthesized from serotonin by the pineal gland in response to darkness. It is the primary regulator of circadian rhythm, signaling the body to prepare for sleep. Exogenous melatonin supplementation (0.5-5 mg) is commonly used for sleep onset latency, jet lag, and shift work disorder. Unlike most sleep medications, melatonin is non-habit-forming and does not suppress REM sleep. Extended-release formulations help with sleep maintenance. Melatonin also functions as a potent antioxidant and has immunomodulatory properties.