Eszopiclone for the treatment of insomnia.

Eszopiclone, a single-isomer, non-benzodiazepine hypnotic agent, is approved for use in the US for the treatment of insomnia for patients who have difficulty falling asleep (sleep latency) as well as for those who have difficulty staying asleep (sleep maintenance). Efficacy in sleep maintenance has not been consistently demonstrated with previous hypnotics, and long-term efficacy and safety data are lacking for these agents. In clinical trials, eszopiclone 3 mg significantly improved objective and subjective sleep measures in transient and chronic insomnia in adults. Nightly treatment with eszopiclone 1 mg effectively induced sleep in elderly patients and the 2-mg dose effectively induced and maintained sleep. The ability of eszopiclone 2 mg to significantly improve next-day functioning and daytime alertness (as demonstrated by a reduction in the number and duration of naps) in the elderly is an important finding in clinical trials, and is unique to the class of hypnotic agents for the treatment of insomnia. Eszopiclone was well tolerated in clinical trials < or = 12 months duration, with no clinically significant evidence of pharmacological tolerance, rebound insomnia or dependence. The most frequently reported adverse event was unpleasant taste. Eszopiclone is the only non-benzodiazepine sedative-hypnotic (in the Schedule IV class under the Controlled Substances Act) to be evaluated as a long-term treatment for chronic insomnia.