How eszopiclone works
Eszopiclone belongs to the group of so-called Z-substances. It promotes sleep by enhancing the effect of the body’s own neurotransmitter GABA (gamma-amino-butyric acid).
GABA is one of the most important neurotransmitters in the brain. By binding to certain docking sites (receptors) on nerve cells, it inhibits the excitability of the cells. As a result, nerve signals have a harder time getting from one nerve cell to the next.
Eszopiclone activates a specific subunit of the GABA receptors. In this way, the active ingredient helps patients to fall asleep and stay asleep. Other GABA effects such as muscle relaxation hardly occur.
Eszopiclone is quickly absorbed into the bloodstream after ingestion as a tablet and takes effect within an hour.
The half-life is around six hours. This means that after this time, the body has already excreted half of the active ingredient. Patients therefore rarely feel tired or unfocused the next morning (the so-called “hang-over effect”).
Zopiclone
The active ingredient zopiclone contained in some sleeping pills is a mixture of two so-called enantiomers. These are compounds that have the same chemical structure but behave like mirror images of each other (like the right and left glove).
In principle, one of two enantiomers is usually more effective, while the other is more likely to trigger side effects. In the case of zopiclone, only the left-turning form, i.e. eszopiclone, is responsible for the sleep-promoting and sedative effect of the drug. The dextrorotatory component, R-zopiclone, on the other hand, is not effective.
How eszopiclone is used
Eszopiclone is available in tablet form. Patients take one milligram directly before going to bed unchewed with a glass of water. In some cases, this dose is not sufficient. The treating doctor then increases it to a maximum of two to three milligrams.
Older patients and patients with previous illnesses react more strongly to eszopiclone. In addition, their bodies break down the active substance more slowly. The doctor therefore reduces the maximum daily dose in some cases. The same applies to patients suffering from severe kidney disease.
Do not take the tablets directly on a full stomach, especially not after a heavy or high-fat meal. Otherwise the effect of eszopiclone may be weakened or delayed.
As a rule, doctors only prescribe eszopiclone for a short period of time. In some cases, however, it is necessary to take the medication for longer, for example in the case of chronic sleep disorders. Doctors then prescribe eszopiclone for a period of up to six months.
What are the side effects of eszopiclone?
In individual cases, eszopiclone triggers memory disorders in the form of anterograde amnesia. This means that those affected no longer remember actions or conversations during the period of the drug’s effect. The symptoms usually occur in the first few hours after taking the medication.
Compared to many other sleeping pills, eszopiclone rarely causes memory problems. Nevertheless, make sure you sleep for at least eight hours without interruption after taking the medication and do not take another dose during the night. This will help you avoid memory problems.
Gastrointestinal disorders are also common side effects of eszopiclone. Patients often have abdominal pain, diarrhea or vomiting. Dry mouth, pharyngitis, sore throat (especially when swallowing) and hoarseness are also possible.
Aching or twitching muscles and back pain are further undesirable side effects that eszopiclone can trigger. A skin rash also often develops.
The appearance of a skin rash may indicate an allergic reaction and should be examined by a doctor. Other allergy symptoms are wheals or very itchy and burning skin.
If patients stop taking eszopiclone, they may need longer to fall asleep during the first few nights. Doctors refer to this as the rebound effect. The symptoms usually improve on their own after one to two days.
When is eszopiclone used?
Doctors prescribe eszopiclone for the short-term treatment of sleep disorders in adult patients. However, they usually only do this if alternatives have not helped sufficiently and the patient is still having difficulty sleeping.
When should eszopiclone not be used?
You must not take eszopiclone if you:
- are hypersensitive to eszopiclone, other components of the medication or zopiclone
- suffer from severe respiratory disorders such as sleep apnoea syndrome (repeated short interruptions in breathing during sleep)
- suffer from myasthenia gravis (an autoimmune disease in which the transmission of nerve signals is impaired)
- have severe liver dysfunction
Children and adolescents must not take eszopiclone as the active ingredient is not approved for this age group.
These interactions can occur with eszopiclone
When eszopiclone is used at the same time as drugs that also have a sedative effect, the effects may be mutually reinforcing. Life-threatening consequences are reduced respiratory drive (respiratory depression) and coma.
Central depressant drugs include
- Tranquilizers (sedatives)
- Sleeping pills (hypnotics)
- Drugs for inducing anesthesia (narcotics)
- Medication for the treatment of psychoses (antipsychotics), e.g. haloperidol
- Medication for the treatment of depression (antidepressants)
- Medication for the treatment of epilepsy (antiepileptic drugs)
- Antihistamines (medication against allergies) such as cetirizine
Alcohol also has a depressant effect. Therefore, avoid alcohol while taking eszopiclone!
The risk of serious side effects increases, especially if patients are taking opioids (for example the painkiller fentanyl) at the same time. Doctors therefore only give eszopiclone in such cases if there is no suitable alternative. They then prescribe the lowest possible dose over a short period of time and pay more attention to adverse reactions. These include
- drowsiness
- confusion
- slowed breathing
- Decreased reflexes
- slowed reactions
- possibly low blood pressure and slowed heartbeat
Eszopiclone is mainly broken down in the liver via the CYP3A4 enzyme system. Some active substances inhibit this enzyme system. When used at the same time as eszopiclone, its breakdown is therefore slowed down – its effects and side effects increase. Such enzyme inhibitors are, for example, certain drugs against fungal infections (azolantimycotics), macrolide antibiotics and grapefruit (as fruit or juice). In these cases, the doctor may reduce the dose of eszopiclone. Older patients who are taking strong enzyme inhibitors must not take the sleeping pill at all (see above: Contraindications).
There are also active substances that accelerate the enzyme system of the liver and thus the breakdown of eszopiclone. These so-called enzyme inducers include rifampicin (antibiotic, mainly for the treatment of tuberculosis), drugs for epilepsy (such as carbamazepine) and the herbal antidepressant St. John’s wort.
As a precaution, tell your doctor and pharmacist about all medicines and food supplements you are taking.
Eszopiclone during pregnancy and breastfeeding
Very little experience is available on the use of eszopiclone during pregnancy. Doctors do not suspect an increased risk of malformations in the unborn child.
To be on the safe side, doctors recommend more suitable medication for pregnant women, for example diphenhydramine in the first two trimesters of pregnancy or sleep-inducing antidepressants such as amitriptyline.
Women who use eszopiclone and are planning a pregnancy or become pregnant should discuss the next steps with their doctor immediately.
In the case of breastfeeding women, doctors decide on a case-by-case basis whether eszopiclone may be taken. If taken over a longer period of time, mothers should stop breastfeeding.
How to obtain medication with eszopiclone
In Germany and Austria, eszopiclone medication can be obtained from pharmacies with a prescription.
There are currently no medicines containing eszopiclone available in Switzerland.
Further important information on eszopiclone
In previous studies, patients hardly developed any tolerance to eszopiclone. This means that the body does not become accustomed to eszopiclone so that the sleeping pill does not lose its effect over time.
Eszopiclone only weakly activates the subunit of the GABA docking site, which causes dependence. Nevertheless, there is a risk of becoming mentally (psychologically) and physically dependent, especially at high doses over a longer period of time. This risk is also increased in patients who are addicted to alcohol, medication or drugs or who suffer from mental illness.