The effects of exogenous melatonin on the total sleep time and daytime alertness of chronic insomniacs: A preliminary study

The effects of exogenous, supraphysiologic doses of melatonin on the total sleep time and daytime alertness of patients with chronic insomnia was examined in a double blind, single crossover study. Melatonin (75 mg per os) or identical placebo was administered at 10 PM daily to 13 insomniac patients for 14 consecutive days. A significant increase in the subjective assessment of total sleep time and daytime alertness was demonstrated with melatonin but not with placebo. However, 7 of the 13 patients reported that the active treatment had no significant effect on subjective feelings of well-being.