Hypnotic efficacy of zaleplon for daytime sleep in rested individuals

Study Objectives: The primary objective of this study was to determine whether zaleplon (10 mg) effectively promoted sleep during the daytime in well-rested individuals when compared to placebo. A secondary objective was to see if, while not expected, the use of zaleplon impacted the performance of well-rested individuals upon awakening. Design: Repeated measures with 2 within-subject factors: drug (placebo/zaleplon) and trial (hourly testing during waking hours). Polysomnographic variables were recorded during a 3.5-hour nap following drug administration. Performance measures and subjective reports were collected during every waking trial of each session. Setting: The study was conducted at the Chronobiology and Sleep Laboratory located at Brooks Air Force Base. Participants: Twelve participants, 6 men and 6 women. Interventions: 10-mg zaleplon or placebo capsules, single afternoon dose. Drug administration was counterbalanced and double-blinded. Measurements and Results: Zaleplon allowed participants to obtain significantly more slow-wave sleep than under placebo. There was also a trend for participants under zaleplon to accomplish a greater amount of sleep than under placebo, Performance was not adversely impacted following a 3.5-hour daytime sleep under zaleplon, nor were any undesirable symptoms induced. Conclusions: Zaleplon improves sleep quality when used by rested individuals to accomplish daytime sleep.