Non-benzodiazepines for the treatment of insomnia.

Benzodiazepine hypnotics, the mainstay of pharmacological treatment for insomnia, have been associated with altered sleep architecture, psychomotor and memory impairment, rebound insomnia, withdrawal effects, tolerance, dependence, abuse potential and respiratory depression. Non-benzodiazepines, such as zolpidem, zopiclone and zaleplon, demonstrate hypnotic efficacy similar to that of benzodiazepines along with excellent safety profiles. Non-benzodiazepines generally cause less disruption of normal sleep architecture than benzodiazepines. Psychomotor and memory impairment may be less problematic with non-benzodiazepines, especially when compared to longer-acting benzodiazepines. Rebound insomnia and withdrawal symptoms occur infrequently upon discontinuation of non-benzodiazepines and may be less common and milder than those seen upon discontinuation of some benzodiazepines. For the long-term treatment of insomnia, which is generally not recommended, zolpidem and zopiclone are particularly good options because they do not develop tolerance rapidly and have a low abuse potential. Limited data indicate that zaleplon has low tolerance and abuse potential, although further experience is needed to determine its long-term efficacy and safety profile. Since non-benzodiazepines produce minimal respiratory depression, they may be safer than benzodiazepines in patients with respiratory disorders. The choice of which hypnotic to use should be based on the patient's primary sleep complaint, health history, adverse effects and cost.