Understanding Zopiclone and Its Use
Zopiclone is a non-benzodiazepine hypnotic agent, commonly known as a 'Z-drug', used for the short-term treatment of insomnia [1.3.4, 1.4.3]. It works by enhancing the effects of a natural brain chemical (GABA) to produce a calming effect, helping individuals fall asleep faster and stay asleep through the night [1.9.2, 1.10.2]. Despite its effectiveness, its use is typically limited to 7-14 consecutive days, and for a maximum of four weeks, to prevent dependence and tolerance [1.3.3, 1.11.4]. Due to potential risks and significant side effects, there are specific groups of people for whom this medication is unsuitable [1.2.2].
Absolute Contraindications: Who Should Never Take Zopiclone
Certain medical conditions are considered absolute contraindications, meaning individuals with these issues should not take zopiclone under any circumstances due to the high risk of severe adverse effects [1.2.1, 1.3.3].
- Myasthenia Gravis: This is a condition that causes severe muscle weakness. Zopiclone can exacerbate this weakness and is strictly contraindicated [1.3.1, 1.3.3, 1.7.1].
- Severe Respiratory Failure: Patients with conditions that severely compromise breathing, such as acute pulmonary insufficiency, should not use zopiclone because it can depress respiratory drive [1.2.1, 1.5.2].
- Sleep Apnea Syndrome: Individuals who stop breathing for short periods while sleeping should avoid zopiclone, as it can worsen this condition [1.3.4, 1.5.2].
- Severe Hepatic Impairment (Liver Disease): The liver is primarily responsible for metabolizing zopiclone. In patients with severe liver problems, the drug is not cleared effectively, which can lead to dangerous levels in the body and precipitate a coma [1.2.1, 1.7.1].
- Hypersensitivity: Anyone with a known allergy to zopiclone or any of its ingredients must not take it. Allergic reactions can include rashes, swelling of the tongue or throat, and difficulty breathing (anaphylaxis) [1.2.2, 1.5.2].
- History of Complex Sleep Behaviors: If a person has previously experienced sleepwalking, sleep-driving, or other unusual behaviors after taking zopiclone, they should not take it again [1.3.4].
Populations Requiring Caution and Dose Adjustment
For some individuals, zopiclone is not strictly forbidden but requires extreme caution and often a reduced dosage. This decision should always be made by a healthcare professional [1.2.2].
- The Elderly (Over 65): Older adults are more sensitive to the effects of zopiclone and are at an increased risk of falls, confusion, and next-day drowsiness [1.3.4, 1.11.3]. A lower starting dose, typically 3.75 mg, is recommended [1.8.4].
- Patients with Liver or Kidney Problems: While severe liver disease is a contraindication, those with mild to moderate liver or kidney issues may be able to take a reduced dose. Zopiclone clearance can be affected, increasing the risk of side effects [1.3.1, 1.8.2].
- Individuals with a History of Mental Health Problems: Zopiclone can unmask or worsen depression and has been associated with suicidal ideation, anxiety, and psychosis [1.2.5, 1.11.2]. Patients with a history of depression or other psychiatric disorders must be monitored closely [1.3.1].
- History of Alcohol or Drug Abuse: There is a greater risk of dependence and abuse in individuals with a history of substance abuse [1.3.1, 1.5.3].
- Pregnancy and Breastfeeding: Zopiclone is generally not recommended during pregnancy as it may harm the developing baby, potentially causing withdrawal symptoms or other issues after birth [1.6.3, 1.11.4]. The drug also passes into breast milk, and its use is not recommended for nursing mothers [1.2.4, 1.6.2].
Dangerous Drug and Substance Interactions
Combining zopiclone with other substances can lead to significantly increased risks, including fatal overdose [1.4.3].
- Alcohol: Mixing zopiclone and alcohol is extremely dangerous. It enhances the sedative effect of both, which can lead to severe drowsiness, respiratory depression, coma, and death [1.4.5, 1.2.5].
- Opioids and other CNS Depressants: Taking zopiclone with opioids (like codeine or morphine), other sedatives, tranquilizers, antidepressants, or antihistamines significantly increases the risk of sedation, breathing difficulties, and coma [1.3.2, 1.5.2].
- CYP3A4 Enzyme Inhibitors/Inducers: Certain drugs affect how the body metabolizes zopiclone [1.4.4].
- Inhibitors (like erythromycin, ketoconazole, and ritonavir) increase zopiclone levels, raising the risk of side effects [1.4.5].
- Inducers (like rifampicin, carbamazepine, and St. John's Wort) decrease zopiclone levels, reducing its effectiveness [1.4.4].
Comparison of Z-Drugs: Zopiclone vs. Zolpidem
Zopiclone and zolpidem are both 'Z-drugs' used for insomnia, but they have different profiles [1.9.1].
| Feature | Zopiclone | Zolpidem |
|---|---|---|
| Primary Use | Better for staying asleep (sleep maintenance) [1.9.1] | Better for falling asleep (sleep onset) [1.9.1] |
| Half-Life | Longer (may cause next-day drowsiness) [1.9.1] | Shorter (less likely to cause next-day drowsiness) [1.9.1] |
| Common Side Effect | Bitter or metallic taste is very common [1.9.3] | Less likely to cause taste disturbance [1.9.3] |
| Rebound Insomnia | Higher potential for rebound insomnia upon stopping [1.9.3] | Lower potential for rebound insomnia [1.9.3] |
Conclusion
While zopiclone can be an effective short-term solution for debilitating insomnia, it is a powerful medication with significant risks and contraindications. It is absolutely essential that it is not taken by individuals with myasthenia gravis, severe respiratory or liver problems, or sleep apnea [1.3.3, 1.3.4]. Special care and lower doses are required for the elderly and those with kidney/liver issues or a history of mental health or substance abuse problems [1.2.2, 1.3.1]. Always consult a healthcare professional to determine if zopiclone is safe for you and to discuss potential interactions with other medications you are taking.
For more information from a trusted health authority, visit the NHS page on Zopiclone.
