Melatonin administration in insomnia.

Ten patients with persistent insomnia were randomized in a double-blind design and the effects of 1-mg and 5-mg oral dosages of melatonin on the electroencephalogram-recorded sleep were examined. Subjects showed no changes in either the onset or duration of sleep, nor any effect on mood or alertness the following day. A significant increase in rapid-eye-movement (REM) latency was noted at the 1-mg dose, though no other parameter of REM sleep was affected. The patients reported less sleep on both melatonin conditions. Despite this perception of decrease, overall subjective quality was reported to be improved.