Zopiclone

Overview of Zopiclone

Zopiclone is a nonbenzodiazepine hypnotic agent of the cyclopyrrolone class. It is a gamma-aminobutyric acid (GABA) receptor agonist, acting selectively on the omega-1 (BZ1) receptor subtype, which produces sedative, anxiolytic, muscle relaxant, and anticonvulsant effects. Primarily indicated for the short-term management of insomnia, zopiclone helps reduce sleep onset latency and improve sleep maintenance. It is typically prescribed for courses not exceeding 2–4 weeks due to the risk of tolerance, dependence, and withdrawal. As a controlled substance in many jurisdictions, zopiclone is available only by prescription and requires careful medical supervision.

Conditions & Treatment Scope

Zopiclone is indicated for the short-term treatment of insomnia, particularly when the condition is severe, disabling, or subjecting the individual to extreme distress. This includes:

• Difficulty falling asleep (onset insomnia)
• Frequent nocturnal awakenings or early morning awakenings (maintenance insomnia)
• Transient or situational sleep disturbances, such as those caused by acute stress, shift work changes, or jet lag

It is not recommended for chronic insomnia, as underlying causes should be investigated and non-pharmacological therapies prioritized. Zopiclone should be administered only after a thorough clinical evaluation and when non-pharmacological measures have proven inadequate.

Important Safety & Precautions

• Contraindications: Known hypersensitivity to zopiclone; severe hepatic impairment; myasthenia gravis; respiratory insufficiency (including sleep apnea syndrome); history of drug or alcohol abuse; children and adolescents under 18 years.
• Dependence and Withdrawal: Physical and psychological dependence can develop, even at therapeutic doses. Abrupt discontinuation after prolonged use may cause withdrawal symptoms such as rebound insomnia, anxiety, tremor, and, in severe cases, seizures or psychosis. Tapering under medical supervision is essential.
• Complex Sleep-Related Behaviours: Rare but serious events like sleepwalking, sleep driving, preparing and eating food, or making phone calls with amnesia have been reported. Discontinue immediately if any such episodes occur.
• CNS Depression: Concomitant use with alcohol, opioids, other sedative-hypnotics, or central nervous system depressants significantly increases the risk of profound sedation, respiratory depression, coma, and death. Use with extreme caution.
• Special Populations: Use during pregnancy and lactation is not recommended; potential risk to the fetus or infant. In elderly or debilitated patients, a lower starting dose is advised due to increased sensitivity to sedative effects and risk of falls.
• Operating Machinery: Zopiclone induces drowsiness and may impair cognitive and motor function the following day. Patients should not drive or engage in hazardous tasks until full alertness is assured and a minimum of 7–8 hours of uninterrupted sleep is guaranteed after dosing.
• Administration: Take zopiclone as a single dose immediately before retiring to bed. Do not redose during the same night. Avoid taking after a heavy or high-fat meal, which may delay onset of action.
• Side Effects: Common adverse effects include bitter or metallic taste, dry mouth, drowsiness, headache, and dizziness. Less commonly, gastrointestinal disturbances, confusion, or anterograde amnesia may occur.