Effects of melatonin on vascular reactivity, catecholamine levels, and blood pressure in healthy men

Am J Cardiol. 1999 May 1;83(9):1417-9. doi: 10.1016/s0002-9149(99)00112-5.


In this study it was investigated whether the oral administration of melatonin (1 mg) in comparison to placebo was able to reduce blood pressure, vascular reactivity, and catecholamines in men, as previously reported in young women. The administration of melatonin significantly reduced blood pressure, the pulsatility index in the internal carotid artery, and catecholamines levels within 90 minutes. The effect of melatonin on the artery pulsatility index was related to baseline values, being greater in men with higher baseline values. The present data indicate that melatonin may blunt the activity of the cardiovascular system and may have both physiopathologic and clinical implications.

Publication types

  • Clinical Trial
  • Randomized Controlled Trial

MeSH terms

  • Adult
  • Blood Pressure / drug effects
  • Cardiovascular System / drug effects*
  • Double-Blind Method
  • Epinephrine / blood
  • Female
  • Free Radical Scavengers / pharmacology*
  • Humans
  • Male
  • Melatonin / pharmacology*
  • Norepinephrine / blood
  • Pulsatile Flow / drug effects
  • Regional Blood Flow / drug effects


  • Free Radical Scavengers
  • Melatonin
  • Norepinephrine
  • Epinephrine