Rebound insomnia: duration of use and individual differences.

This study assessed consistency, duration of use, and individual difference in rebound insomnia. Eleven healthy men, 20-30 years old, with normal sleep by both subjective and polysomnographic criteria, received each of four treatments in a double-blind Latin Square design (triazolam 0.50 mg for 1, 6, and 12 nights and placebo for 12 nights), followed by two placebo discontinuation nights. Triazolam increased sleep compared with placebo without differences in effects between the first and last nights of treatment. On discontinuation following active drug, sleep efficiency was reduced compared with placebo, but duration of administration did not alter the likelihood or intensity of rebound insomnia. Those subjects (5) showing poorer sleep on discontinuation from the 12-night treatment also had poorer sleep in the 1- and 6-night treatment. Subjects with rebound insomnia had poorer baseline sleep and a greater drug effect than did subjects without.