|Summary sheet: Zopiclone|
|Common names||Zimovane, Imovane|
|Systematic name||(RS)-6-(5-Chloropyridin-2-yl)-7-oxo-6,7-dihydro-5H-pyrrolo[3,4-b]pyrazin-5-yl 4-methylpiperazine-1-carboxylate|
|Psychoactive class||Depressant / Hallucinogen|
|Routes of Administration|
Zopiclone (also known by the trade names Zimovane and Imovane) is a non-benzodiazepine hypnotic substance of the cyclopyrrolone class that is primarily used in the treatment of insomnia. Zopiclone is known to belong to a family of drugs colloquially known as "Z-drugs". Other Z-drugs include zaleplon (Sonata) and zolpidem (Ambien and AmbienCR).
Zopiclone is thought to increase the normal neurotransmission of the neurotransmitter GABA in the central nervous system in a similar yet distinct way to the activity of benzodiazepines. As zopiclone displays heavy sedating effects, it is has been approved for and is commonly sold as a sleeping pill.
While "Z-drugs" were initially thought to have less misuse potential than benzodiazepines, this appraisal has shifted somewhat in the last few years as a number of cases of addiction and habituation have been observed. Zopiclone, like all "Z-drugs", is recommended to be taken on a short-term basis -- usually a week or less. Daily or continuous use of the drug is usually not advised.
Zopiclone is a hypnotic nonbenzodiazepine drug of the cyclopyrrolone class. Zopiclone and its closely related dextrorotatory S-stereoisomer zopiclone (Lunesta) are the most popular and available cyclopyrrolone drugs. This class of drugs is named for having a pyrrolone core, a five-membered ring with a nitrogen constituent (pyrrole) and a ketone group (-one).
The ketone group found in zopiclone is located at R5 of the pyrrolone ring. Zopiclone contains four nitrogenous rings including pyrrolone. Fused to the pyrrolone core is a pyrazine ring, a six-membered aromatic ring with two nitrogen substituents. The two rings are fused at R3 and R4. This bicylic core is called a pyrollopyrazine. Bound to the nitrogen group of the pyrrolone at R6 is a substituted pyridine ring. Pyridine is six-membered unsaturated ring with one nitrogen group. The pyridine ring of zopiclone is substituted at R5 with a chlorine group.
The final ring of zopiclone is a piperazine ring. Piperazine is a six-membered saturated ring with two nitrogen constituents; in this case, it is substituted at R4 with a methyl group. This piperazine ring is connected to the pyrrolone core of zopiclone at R7 through a carboxylate group.
Zopiclone may be measured in blood, plasma, or urine by chromatographic methods. Plasma concentrations are typically less than 100 μg/l during therapeutic use, but frequently exceed 100 μg/l in automotive vehicle operators arrested for impaired driving ability and may exceed 1000 μg/l in acutely poisoned patients. Post mortem blood concentrations are usually in a range of 0.4-3.9 mg/l in victims of fatal acute overdose.
Zopiclone, although structurally different from benzodiazepines, shares an almost identical pharmacological profile to them. Its mechanism of action works by binding to the same site as benzodiazepines and acts as a full agonist, which in turn positively modulates benzodiazepine-sensitive GABAA receptors and enhances GABA binding at the GABAA receptors to produce zopiclone's subjective effects. Since GABA functions as the brain's predominant inhibitory neurotransmitter, this activation of receptors results in the sedative and anxiolytic effects of zopiclone. In addition to zopiclone's benzodiazepine pharmacological properties, it also has some barbiturate-like properties.
The metabolite of zopiclone called desmethylzopiclone is also pharmacologically active, although it has predominately anxiolytic properties. One study found some slight selectivity for zopiclone on α1 and α5 subunits, although it is regarded as being unselective in its binding to α1, α2, α3, and α5 GABAA benzodiazepine receptor complexes. Desmethylzopiclone has been found to have partial agonist properties, unlike the parent drug zopiclone, which is a full agonist. The mechanism of action of zopiclone is similar to benzodiazepines, with similar effects on locomotor activity and on dopamine and serotonin turnover.
In comparison to other substances of a similar nature such as benzodiazepines, zopiclone is commonly reported to present significantly more amnesic and disinhibiting effects in a manner similar to alcohol.
Disclaimer: The effects listed below cite the Subjective Effect Index (SEI), a research literature based on anecdotal reports and the personal experiences of PsychonautWiki contributors. As a result, they should be regarded with a healthy degree of skepticism. It is worth noting that these effects will not necessarily occur in a predictable or reliable manner, although higher doses are more liable to induce the full spectrum of effects. Likewise, adverse effects become much more likely with higher doses and may include addiction, serious injury, or death.
- Sedation - zopiclone is extremely sedating and can put the user into an overwhelmingly lethargic state. At higher levels, this causes users to suddenly feel as if they are extremely sleep deprived and have not slept for days, forcing them to sit or lay down and feel as if they are constantly on the verge of passing out. This sense of sleep deprivation increases proportional to dosage and can eventually become powerful enough to force a person into complete unconsciousness regardless of where they are or what they are doing at that moment.
- Respiratory depression
- Muscle relaxation
- Motor control loss - This effect is pronounced and comparable to the motor control loss experienced on a heavy dose of alcohol. This typically results in users stumbling and an inability to walk in a straight line. As this may easily result in injury, one should avoid walking and using stairs while on zopiclone.
- Gustatory hallucination - Zopiclone is sometimes reported to leave a metallic taste in one's mouth.
- Shadow people
- Acuity suppression
- Drifting (melting, breathing, morphing and flowing) - Visual drifting effects are the most prominent visual effects of this substance. They typically occur at strong doses, or when the user resists the urge to sleep.. They are similar to the distortions produced zolpidem and are usually less pronounced than those of deliriants. Like deliriant visuals, they are most prominent in low lighting. Depending on dose and lighting, they can be described as slow or fast in speed, static in permanence, smooth in motion, realistic in appearance, and simplistic or intricate.
- External hallucinations - At very high doses, zopiclone can produce external hallucinations that are similar to, but less pronounced than those of deliriants.
- Tracers - This effect is mild and typically only experienced at high doses.
The cognitive effects of zopiclone can be broken down into several components which progressively intensify proportional to dosage. The general head space of zopiclone is described by many as one of intense sedation, decreased inhibition and severe amnesia. It produces a large number of cognitive effects typical of most GABA-ergic depressants.
- Amnesia - Compared to benzodiazepines, zopiclone can produce amnesia at much lower doses. One may potentially not remember exactly what happened while under the influence of a common dose. This is usually less intense than the amnesia produced by zolpidem.
- Anxiety suppression
- Thought deceleration
- Analysis suppression
- Euphoria - Some users report euphoria from zopiclone, although this is short lived and usually exclusive to the onset of the experience and often followed by emotion suppression.
- Emotion suppression - While zopiclone primarily suppresses anxiety, it also suppresses other emotions in a similar but less intense fashion to antipsychotics.
- Time compression - This effect is mostly noticeable while under the influence of a high dose.
- Irritability - Combined with the strong disinhibiting effects of zopiclone, this effect can cause people under the influence of zopiclone to have violent behavior towards others and sometimes themselves.
- Increased music appreciation
- Compulsive redosing
Anecdotal reports which describe the effects of this compound within our experience index include:
Additional experience reports can be found here:
Toxicity and harm potential
By itself, zopiclone likely has a low toxicity relative to dose. However, it is potentially lethal when mixed with depressants like benzodiazepines, alcohol or opioids. When combined with one or several of these drugs the already existing chance of a having a "black-out" is significantly increased, leaving the user with very little to no memory of the events that occurred whilst under the influence of zopiclone alone or combined with most other CNS depressants. Users have reported taking zopiclone in combination with alcohol in an attempt to treat hangovers with varying degrees of success.
It is strongly recommended that one use harm reduction practices when using this substance.
Tolerance and addiction potential
Zopiclone is extremely physically and psychologically addictive. This compound may have an even greater addictive potential than benzodiazepines. Tolerance will develop to the sedative-hypnotic effects within a couple of weeks of daily use. After cessation, the tolerance returns to baseline in 7 - 14 days. Withdrawal symptoms or rebound symptoms may occur after ceasing usage abruptly following a few weeks or longer of steady dosing, and may necessitate a gradual dose reduction.
Although many psychoactive substances are reasonably safe to use on their own, they can suddenly become dangerous or even life-threatening when combined with other substances. The following list includes some known dangerous combinations (although it is not guaranteed to include all of them). Independent research (e.g. Google, DuckDuckGo) should always be conducted to ensure that a combination of two or more substances is safe to consume. Some of the listed interactions have been sourced from TripSit.
- Depressants (1,4-Butanediol, 2-methyl-2-butanol, alcohol, barbiturates, GHB/GBL, methaqualone, opioids) - This combination can result in dangerous or even fatal levels of respiratory depression. These substances potentiate the muscle relaxation, sedation and amnesia caused by one another and can lead to unexpected loss of consciousness at high doses. There is also an increased risk of vomiting during unconsciousness and death from the resulting suffocation. If this occurs, users should attempt to fall asleep in the recovery position or have a friend move them into it.
- Dissociatives - This combination can result in an increased risk of vomiting during unconsciousness and death from the resulting suffocation. If this occurs, users should attempt to fall asleep in the recovery position or have a friend move them into it.
This legality section is a stub.
As such, it may contain incomplete or wrong information. You can help by expanding it.
- Canada: Zopiclone is available by prescription only in Canada.
- Germany: Zopiclone is a prescription medicine, according to Anlage 1 AMVV
- Norway: Zopiclone is available by prescription in Norway.
- Switzerland: Zopiclone is listed as a "Abgabekategorie B" pharmaceutical, which generally requires a prescription.
- Risks of Combining Depressants (Tripsit) | https://tripsit.me/combining-depressants/
- Effects of zopiclone and temazepam on sleep, behaviour and mood during the day (PubMed.gov / NCBI) | http://www.ncbi.nlm.nih.gov/pubmed/2744064
- Kratzsch C, Tenberken O, Peters FT et al. Screening, library-assisted identification, and validated quantification of 23 benzodiazepines, flumazenil, zaleplone, zolpidem, and zopiclone in plasma by liquid chromatography/mass spectrometry with atmospheric pressure chemical ionization. J. Mass Spec. 39: 856-872, 2004.
- Petroski RE, Pomeroy JE, Das R, et al. (April 2006). "Indiplon is a high-affinity positive allosteric modulator with selectivity for alpha1 subunit-containing GABAA receptors". Journal of Pharmacology and Experimental Therapeutics. 317 (1): 369–377. doi:10.1124/jpet.105.096701. PMID 16399882. S2CID 46510829.
- Atack, J.R. (August 2003). "Anxioselective compounds acting at the GABA(A) receptor benzodiazepine binding site". Current Drug Targets. CNS & Neurological Disorders. 2 (4): 213–332. doi:10.2174/1568007033482841. PMID 12871032.
- Zopiclone and triazolam in insomnia associated with generalized anxiety disorder. If zopiclone has been taken for more than a few weeks, then the medication should be gradually reduced or preferably crossed over to an equivalent dose of diazepam (Valium) which has a much longer half-life, making withdrawal easier. One should then gradually taper the dose over a period of several months to avoid extremely severe and unpleasant withdrawal symptoms which can last up to two years after withdrawal if the withdrawal is done too abruptly. http://www.benzo.org.uk/manual/