Although Jacques Montplaisir may be correct in his assertion that shorter and longer acting benzodiazepines differ in their profiles of adverse effects on the central nervous system, this was not evident in our systematic review.1 Many of the studies published on amnesia and rebound insomnia have involved triazolam, a potent benzodiazepine with one of the shortest half-lives of the group. However, these and other cognitive impairment effects have been ascribed to all benzodiazepines.2,3 We remind readers that no benzodiazepine is reliably short acting in terms of sedation in elderly patients with comorbidity, particularly if doses are not adjusted downward.4,5,6 There has been virtually no research on therapeutic strategies for insomnia involving this group of patients, who are arguably the highest per capita users of benzodiazepines and alternatives.
Zopiclone is an interesting nonbenzodiazepine sedative. Unlike Montplaisir, we are not convinced that it is superior in efficacy or safety to all benzodiazepines. Studies involving zopiclone tend to be disabled by the use of suboptimal benzodiazepines for comparison (very-long-acting benzodiazepines are used instead of shorter acting drugs similar to zopiclone), small patient numbers and concerns regarding dose equivalence. Our systematic review of 9 randomized controlled trials including 3 appropriate for meta-analysis did not suggest that zopiclone is superior for sleep.1 A separate meta-analysis of sleep laboratory studies also noted the paucity of high-quality studies involving zopiclone, but the available studies suggest that it is similar to shorter acting benzodiazepines in efficacy, tolerance and rebound.7 Several studies have noted that zopiclone has adverse effects on human performance similar to those seen with benzodiazepines.8,9,10,11 Finally, although it represents a lower quality of evidence according to our criteria, we are highly persuaded by the zopiclone manufacturer‚s own product monograph (monographs are often based on information not available for public scrutiny) that ”the pharmacological profile of zopiclone is similar to that of the benzodiazepines.”12
In this issue
Article tools
Jump to section
Related Articles
Cited By...
- No citing articles found.
More in this TOC Section
Similar Articles
