Next-day residual effects of gaboxadol and flurazepam administered at bedtime: a randomized double-blind study in healthy elderly subjects

Abstract

Objective: To evaluate the next-day residual effects of the novel hypnotic, gaboxadol, following bedtime dosing in healthy elderly subjects.

Methods: Healthy women (N = 15) and men (N = 10) aged 65-79 years received a single bedtime (22:00 h) dose of gaboxadol 10 mg, flurazepam 30 mg (positive control), and placebo in a randomized, double-blind, crossover study. Measures of information processing and psychomotor performance (choice reaction time, critical flicker fusion, digit symbol substitution, compensatory tracking, body sway), memory (immediate and delayed word recall), and daytime sleepiness (Multiple Sleep Latency Test), as well as subjective ratings (line analog rating scales, Leeds Sleep Evaluation Questionnaire), were obtained starting at 07:00 h the following morning. Adverse events were recorded.

Results: Gaboxadol did not show next-day impairments versus placebo on any pharmacodynamic measures whereas the positive control, flurazepam, did show impairments versus placebo on most measures. Gaboxadol showed improvements versus placebo on some measures including subjective rating of next-day alertness/clumsiness on the Leeds Sleep Evaluation Questionnaire. Gaboxadol was generally well-tolerated; there were no serious adverse experiences and no subjects discontinued due to an adverse experience.

Conclusions: A single oral bedtime dose of gaboxadol 10 mg did not have next-day residual effects in healthy elderly subjects, as measured by a range of pharmacodynamic assessments, in contrast to the clear impairments produced by flurazepam 30 mg.