A five week, polysomnographic assessment of zaleplon 10 mg for the treatment of primary insomnia

Objective: To examine the hypnotic efficacy of zaleplon 10 mg, a selective benzodiazepine receptor agonist, over a period of 35 nights in primary insomniacs. Methods: A double-blind, parallel-group, placebo-controlled design was employed. Subjects were 113 men and women, ages 18 to 65 years. Polysomnographic and subjective sleep data were collected during baseline, on two nights during each of five treatment weeks, and on the first two nights after discontinuation of active medication. Results: Sleep latency was significantly shortened with zaleplon 10 mg for all 5 weeks of treatment as assessed by polysomnography and by subjective sleep measures. Total sleep time, whether evaluated with polysomnography or with subjective estimates, was inconsistently affected. Sleep architecture was similar with zaleplon and placebo. There was no evidence of tolerance to the sleep promoting effects of zaleplon during the five weeks of administration, and there was no rebound insomnia upon discontinuation. Adverse events occurred with equal frequency in the zaleplon and placebo groups. Conclusions: Zaleplon 10 mg is effective in the treatment of sleep onset insomnia over a period of 35 nights, with minimal evidence of undesired effects. (C) 2000 Elsevier Science B. V. All rights reserved.