Zopiclone
Indications
Zopiclone is used for:
Insomnia
Adult Dose
Oral
Short-term management of insomnia
Adult: 7.5 mg at bedtime.
Elderly: Initially, 3.75 mg at bedtime.
Hepatic impairment: Mild to moderate: Initially 3.75 mg at bedtime. Severe: Contraindicated.
Child Dose
Child: Not recommended.
Renal Dose
Renal impairment: Initiate at 3.75 mg at bedtime.
Administration
May be taken with or without food.
Contra Indications
Myasthenia gravis; respiratory failure; severe sleep apnoea syndrome; severe hepatic impairment; pregnancy, lactation.
Precautions
Hepatic and renal insufficiency; elderly; psychiatric disorders; history of drug abuse. May impair ability to drive or operate machinery. Limit treatment duration to <4 wk to minimise risk of dependence and tolerance. Avoid abrupt discontinuation of therapy.
Pregnancy-Lactation
Interactions
Reduced hypnotic effect with phenytoin and carbamazepine. Increased drowsiness and incoordination with TCAs. Increased CNS depressant effect with alcohol and other CNS depressants. Decreased zopiclone concentration with rifampicin. Possible increase in zopiclone concentration with CYP3A4 inhibitors e.g. erythromycin, clarithromycin, ketoconazole, itraconazole, ritonavir.
Adverse Effects
Side effects of Zopiclone :
Metallic or bitter aftertaste; irritability, confusion, depressed mood, aggressiveness, incoordination, anterograde amnesia, mild increase in LFTs, drowsiness, lightheadedness, nausea, vomiting, urticaria, rashes.
Mechanism of Action
Zopiclone is a cyclopyrrolone derivative with hypnotic and sedative actions, anticonvulsant and muscle relaxant properties similar to benzodiazepines. It binds to a site in the GABA-A-benzodiazepine-chloride channel macromolecular-receptor complex which is different from that of the benzodiazepine binding site.