Acute administration of triazolam for the daytime sleep of rotating shift workers.

Ten rotating shift workers, who changed shifts every 1 to 4 weeks, slept in the laboratory during the first four daytime sleep periods of two consecutive tours of night shift. Prior to the first two sleep periods of one tour, the subjects were given 0.5 mg triazolam. Placebo was administered prior to sleep periods one and two of the other night shift tour. Neither drug nor placebo was given before the third and fourth sleep period of either tour of night shift. Conditions were counterbalanced among subjects. Polysomnography demonstrated that triazolam significantly increased total sleep time and sleep efficiency relative to placebo, primarily by promoting sleep maintenance. No adaptation to daytime sleep was seen during the four consecutive sleep periods without triazolam (placebo, then no drug). Triazolam did not appear to promote adaptation to daytime sleep on the 2 days following triazolam administration.