Zopiclone: is it a pharmacologic agent for abuse?

OBJECTIVE

To determine whether the hypnosedative drug zopiclone could be an agent for abuse.

SOURCES OF INFORMATION

Using MEDLINE and PubMed, English-language medical literature was systematically reviewed for reports of direct drug abuse and addiction. A review was also conducted for clinical trials or patient series that discussed issues of addiction or rebound effects.

MAIN MESSAGE

Evidence of drug abuse and dependency was found in case reports and small patient series. Dependency symptoms of severe rebound, severe anxiety, tremor, palpitations, tachycardia, and seizures were observed in some patients after withdrawal. Abuse occurred more commonly among patients with previous drug abuse or psychiatric illnesses. Many clinical trials have found evidence of rebound insomnia after recommended dosages were stopped, albeit for a minority of patients. Comparative studies of zopiclone and benzodiazepines or other "Z" drugs are conflicting.

CONCLUSION

Zopiclone has the potential for being an agent of abuse and addiction. While many have suggested that the addictive potential for this and other "Z" drugs is less than for most benzodiazepines, caution should be taken when prescribing this agent for insomnia. Ideally, prescriptions should be given for a short period of time and within the recommended dosage guidelines.