Physical dependence on zopiclone: case reports.

Over the past few decades there has been a reluctance to prescribe benzodiazepines for insomnia and anxiety, as evidence for dependence and withdrawal has accumulated. Alternative treatments have therefore been sought. Zopiclone, a cyclopyrrolone, is chemically unrelated to benzodiazepines but acts via the benzodiazepine/ãaminobutyric acid receptor complex. It is licensed for the short term treatment of insomnia. Claims that zopiclone does not cause rebound, dependence, or withdrawal phenomena may have led to it being considered a safe option for treating insomnia. We present a series showing evidence of zopiclone dependence and problems caused by withdrawal.