Melatonin — Supplements

Endogenous neurohormone regulating circadian rhythm and sleep-wake cycles with potent antioxidant properties.

Overview

Melatonin is a neurohormone produced by the pineal gland in response to darkness, serving as the primary zeitgeber (time-giver) for circadian rhythm regulation. It acts on MT1 and MT2 receptors in the suprachiasmatic nucleus to promote sleep onset. Beyond sleep, melatonin is a powerful antioxidant with anti-inflammatory and immunomodulatory properties. Strong evidence supports its use for sleep onset latency reduction, jet lag management, and circadian rhythm disorders. Melatonin production declines with age, contributing to age-related sleep disturbances.

Indications

  • Sleep onset latency reduction
  • Jet lag management
  • Circadian rhythm disorder treatment
  • Shift work sleep disorder
  • Antioxidant and immune support

Mechanism of Action

Binds to melatonin receptors in the suprachiasmatic nucleus, promoting sleep and synchronizing circadian rhythms

Dosing

CompoundDoseFrequencyNotes
Melatonin0.5-3 mg30-60 min before bedtimeStart at 0.5 mg; increase only if needed; sublingual for faster onset

Evidence Grade

GRADE C

Safety & Contraindications

  • Start with lowest effective dose (0.5-1 mg); higher doses are not necessarily more effective
  • May cause next-day grogginess, vivid dreams, or headache
  • Avoid in autoimmune conditions (immune-stimulatory effects)
  • May interact with anticoagulants, diabetes medications, and immunosuppressants
  • Exogenous melatonin at physiological doses does not suppress endogenous production