Benzodiazepines and Z-drugs · Psychiatry
Zopiclone
Z-drug · Imovane®(brand names vary by market)
A hypnotic marketed as safer than a benzodiazepine, on evidence that has not held up.
Mechanism
A cyclopyrrolone acting at the same GABA-A benzodiazepine site; structurally different, pharmacologically similar.
Indications
- Short-term treatment of insomnia
Formulations
Dosing concepts
Duration
Licensed and evidenced for short courses of days to a couple of weeks. Beyond that the benefit fades and the harms accumulate.
Older adults
Doses are halved, and even then the fall and next-morning impairment data are unfavourable enough that non-drug management is preferred.
Concepts, not prescribing instructions. Practice numbers live in current references and local protocols.
Pharmacokinetics
- Bioavailability
- ~75%
- Half-life
- ~5 h, longer in older adults and hepatic impairment
- Elimination
- hepatic: CYP3A4 and CYP2C8
- Protein binding
- ~45%
Adverse effects
- Bitter metallic tastecommonCharacteristic, and the reason many patients recognise it.
- Next-morning sedation and impaired drivingcommon & seriousMeasurable at standard doses, and worse in older adults.
- Falls and fracturesserious
- Complex sleep behavioursseriousSleep-walking, sleep-driving and sleep-eating are described and are a reason to stop permanently.
- Dependence and rebound insomniacommon
Contraindications & precautions
Contraindications
- Severe respiratory failure
- Severe hepatic impairment
- Sleep apnoea
- Myasthenia gravis
Precautions
- Older adults
- Concurrent opioids or alcohol
- History of substance use
- Occupational driving
Interactions
No curated interaction entries yet for this agent.
Monitoring
Duration of use and whether it is still needed
The commonest problem with this drug is that nobody stops it
Falls, confusion and next-morning function
Under-recognised harms
Sleep quality against non-drug measures
Cognitive behavioural therapy for insomnia outperforms it and lasts
Counselling points
- Take it immediately before bed, and only when you can allow a full night's sleep.
- Do not drink alcohol with it.
- Be careful driving the next morning: the effects can persist.
- This is a short course. If sleep is still a problem afterwards, there are better long-term approaches.
Clinical pearls
- Rebound insomnia on stopping is often mistaken for the original problem returning, which is how a two-week prescription becomes a two-year one. Warning the patient in advance changes that.
- The claim that Z-drugs are meaningfully safer than benzodiazepines does not survive the fracture and road-traffic data.
References & review
- Zopiclone product monograph (consult the current version for your market) (monograph)
- Goodman & Gilman's The Pharmacological Basis of Therapeutics, 14th ed. (reference-work)
Last reviewed 2026-08-16 · jurisdiction: global · drug information changes; verify against current references before practice use.