Sleep-promoting effects of melatonin: at what dose, in whom, under what conditions, and by what mechanisms?

Sleep. 1997 Oct;20(10):908-15. doi: 10.1093/sleep/20.10.908.


Differing conclusions regarding the sleep-promoting effects of melatonin may be the result of the broad range of doses employed (0.1-2000 mg), the differing categories of subjects tested (normal subjects, insomniac patients, elderly, etc.), and the varying times of administration (for daytime vs. nighttime sleep). We conclude that melatonin may benefit sleep by correcting circadian phase abnormalities and/or by a modest direct soporific effect that is most evident following daytime administration to younger subjects. We speculate that these effects are mediated by interactions with specific receptors concentrated in the suprachiasmatic nucleus (SCN) that result in resetting of the circadian pacemaker and/or attenuation of an SCN-dependent circadian alerting process.

Publication types

  • Research Support, U.S. Gov't, P.H.S.
  • Review

MeSH terms

  • Adult
  • Aged
  • Body Temperature Regulation / drug effects
  • Circadian Rhythm / drug effects
  • Humans
  • Hypnotics and Sedatives / therapeutic use*
  • Melatonin / pharmacology
  • Melatonin / therapeutic use*
  • Middle Aged
  • Sleep Initiation and Maintenance Disorders / drug therapy*
  • Suprachiasmatic Nucleus / drug effects
  • gamma-Aminobutyric Acid / drug effects


  • Hypnotics and Sedatives
  • gamma-Aminobutyric Acid
  • Melatonin