Zolpidem in the treatment of transient insomnia: a double-blind, randomized comparison with placebo.

Transient insomnia may be induced by stress, sleep in unfamiliar surroundings, jet lag and other factors. Zolpidem, a novel imidazopyridine hypnotic, has been shown to have hypnotic properties in most patients without significantly affecting next-day performance. Using the first-night effect in a sleep laboratory as a model of transient insomnia, this placebo-controlled, double-blind, parallel-group study evaluated the efficacy and safety of zolpidem in 462 normal volunteers. Zolpidem was tested at doses of 5, 7.5, 10, 15 and 20 mg, and statistical analysis of 7.5 mg and 10 mg was compared with placebo (unbalanced randomization). Compared with placebo, the 7.5 mg and 10 mg doses of zolpidem decreased sleep latency and increased sleep duration and maintenance (i.e. reduced number of awakenings). Zolpidem (7.5 mg or 10 mg) had no significant effect on next-day psychomotor performance. No statistically significant differences in the overall side-effect profiles were found between 7.5-mg and 10-mg zolpidem dose groups and placebo. This study demonstrates that zolpidem at 7.5 mg and 10 mg is effective in the treatment of transient insomnia.