Residual effects of eszopiclone and placebo in healthy elderly subjects: a randomized double-blind study.

Next-day residual effects are a common problem with current hypnotics. The purpose of the present study was to evaluate the residual effects of eszopiclone on the physical and cognitive functions of healthy elderly people in the early morning and the day following drug administration. Four men and six women aged 63-72 years were administered eszopiclone 1 mg or placebo in a randomized, double-blind and crossover design. Measures of objective parameters and subjective ratings were obtained at 4:00, 6:00, and every 2 h from 6:00 to 16:00 hours. For the timed up-and-go test, the main effects of time were seen. For the critical flicker fusion, eszopiclone had significantly worse results compared to placebo in early morning (4:00). There were no significant differences between eszopiclone and placebo in other objective assessments. For the sleep latency, eszopiclone had significantly shorter results compared to placebo (eszopiclone vs placebo = 28.4 vs 52.5 min,  = 0.047). Feeling of deep sleep and the number of wake after sleep onset did not show any significant differences between eszopiclone and placebo. Based on the above results, the changes of physical and cognitive functions in the healthy elderly after taking hypnotics, it was found that eszopiclone 1 mg is likely to be unharmful for the healthy elderly. Further studies of elderly insomniacs with midnight awakenings are needed.