Zopiclone

Zopiclone

Clinical data
Trade names	Imovane, Zimovane, Dopareel, others
AHFS/Drugs.com	International Drug Names
Pregnancy category	AU: C
Routes of administration	Oral tablets, 3.75 mg or 7.5mg (UK), 5 mg, 7.5 mg, or 10 mg (JP)
ATC code	N05CF01 (WHO)
Legal status
Legal status	AU: S4 (Prescription only) BR: Class B1 (Psychoactive drugs)[1] CA: ℞-only NZ: Class C UK: Class C US: Schedule IV In general: ℞ (Prescription only)
Pharmacokinetic data
Bioavailability	75–80%[2]
Protein binding	52–59%
Metabolism	Hepatic through CYP3A4 and CYP2E1
Elimination half-life	~5 hours (3.5–6.5 hours) ~7–9 hours for 65+ years old
Excretion	Urine (80%)
Identifiers
IUPAC name (RS)-6-(5-chloropyridin-2-yl)-7-oxo-6,7-dihydro-5H-pyrrolo[3,4-b]pyrazin-5-yl 4-methylpiperazine-1-carboxylate
CAS Number	43200-80-2 Y
PubChem CID	5735
IUPHAR/BPS	7430
DrugBank	DB01198 Y
ChemSpider	5533 Y
UNII	03A5ORL08Q
KEGG	D01372 Y
ChEBI	CHEBI:32315 Y
ChEMBL	ChEMBL135400 Y
PDB ligand	ZPC (PDBe, RCSB PDB)
CompTox Dashboard (EPA)	DTXSID4041155
ECHA InfoCard	100.051.018
Chemical and physical data
Formula	C17H17ClN6O3
Molar mass	388.81 g·mol−1
3D model (JSmol)	Interactive image
SMILES O=C(OC3c1nccnc1C(=O)N3c2ncc(Cl)cc2)N4CCN(C)CC4
InChI InChI=1S/C17H17ClN6O3/c1-22-6-8-23(9-7-22)17(26)27-16-14-13(19-4-5-20-14)15(25)24(16)12-3-2-11(18)10-21-12/h2-5,10,16H,6-9H2,1H3 Y Key:GBBSUAFBMRNDJC-UHFFFAOYSA-N Y
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Zopiclone, sold under the brand name Imovane among others, is a nonbenzodiazepine, specifically a cyclopyrrolone, used to treat difficulty sleeping. Zopiclone is molecularly distinct from benzodiazepine drugs and is classed as a cyclopyrrolone. However, zopiclone increases the normal transmission of the neurotransmitter gamma-aminobutyric acid (GABA) in the central nervous system, via modulating GABA_A receptors similarly to the way benzodiazepine drugs do inducing sedation but not with the anti-anxiety properties of the benzodiazepines.

Zopiclone is a sedative. It works by causing a depression or tranquilization of the central nervous system. After prolonged use, the body can become accustomed to the effects of zopiclone. When the dose is then reduced or the drug is abruptly stopped, withdrawal symptoms may result. These can include a range of symptoms similar to those of benzodiazepine withdrawal. Although withdrawal symptoms from therapeutic doses of zopiclone and its isomers (i.e., eszopiclone) do not typically present with convulsions and are therefore not considered life-threatening, patients may experience such significant agitation or anxiety that they seek emergency medical attention. ^{[citation needed]}

In the United States, zopiclone is not commercially available,^[3] although its active stereoisomer, eszopiclone, is. Zopiclone is a controlled substance in the United States, Japan, Brazil, New Zealand and some European countries, and may be illegal to possess without a prescription. ^{[citation needed]}

Zopiclone is known colloquially as a "Z-drug". Other Z-drugs include zaleplon and zolpidem and were initially thought to be less addictive than benzodiazepines. However, this appraisal has shifted somewhat in the last few years as cases of addiction and habituation have been presented. Zopiclone is recommended to be taken at the lowest effective dose, with a duration of 2–3 weeks for short-term insomnia.^[4] Daily or continuous use of the drug is not usually advised, and caution must be taken when the compound is used in conjunction with benzodiazepines, sedatives or other drugs affecting the central nervous system.^[5]