EFFECTS OF ESTAZOLAM AND TRIAZOLAM ON TRANSIENT INSOMNIA ASSOCIATED WITH PHASE-SHIFTED SLEEP

Forty-eight healthy volunteers with a normal sleep/wake history participated in a two-centre, double-blind, parallel group study comparing the effects of estazolam 2.0 mg, triazolam 0.25 mg, and placebo on sleep, performance and alertness following 180 degree reversal in sleep/wake schedule. Sleep-phase reversal produced decreased sleep time, primarily during the last 2 hours of the sleep period. Estazolam prevented this transient insomnia by maintaining sleep in the latter part of the sleep period. Triazolam did not significantly change total sleep time, which was intermediate between that of the estazolam and placebo groups. Neither active compound produced significant effects on subsequent performance or alertness.