Low, but not high, doses of melatonin entrained a free-running blind person with a long circadian period

Alfred J. Lewy, Jonathan S. Emens, Robert L. Sack, Brant P. Hasler, Rebecca A. Bernert

Research output: Contribution to journalArticle

71 Scopus citations


In a previous report, we were unable to entrain one out of seven totally blind people with free-running endogenous melatonin rhythms to 10 mg of exogenous melatonin. This person had the longest circadian period (24.9 h) of the group. We now find that this person can be entrained to 0.5 mg of melatonin, but not to 20 mg. These results are consistent with the idea that too much melatonin may spill over onto the wrong zone of the melatonin phase-response curve.

Original languageEnglish (US)
Pages (from-to)649-658
Number of pages10
JournalChronobiology International
Issue number3
StatePublished - Jun 17 2002



  • Circadian rhythms
  • Free-running totally blind people
  • Melatonin
  • Melatonin phase-response curve

ASJC Scopus subject areas

  • Physiology
  • Physiology (medical)

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