Eszopiclone (Lunesta)
A z-drug that helps with both falling asleep and staying asleep, known for a distinctive bitter aftertaste.
What it treats
Eszopiclone is approved by the U.S. Food and Drug Administration for the treatment of insomnia. It can help with both the trouble falling asleep and the trouble staying asleep that insomnia involves, which sets it apart from z-drugs that mainly help at the start of the night.
It treats the symptom of poor sleep rather than its underlying cause. For insomnia that has lasted weeks or months, cognitive behavioral therapy for insomnia, often shortened to CBT-I, is the recommended first-line treatment. It works on the habits and thoughts that keep insomnia going, and its benefits tend to outlast treatment. Eszopiclone can have a place alongside that work, but it isn't a long-term fix on its own.
How it works
Eszopiclone acts on the GABA-A receptor, the same receptor that benzodiazepines act on. GABA is the brain's main calming chemical messenger, and increasing its signal quiets brain activity and promotes sleep.
What distinguishes the z-drugs is how selectively they bind. Eszopiclone attaches more specifically to a receptor subtype tied to sedation, so its effect is more purely sleep-promoting. It has less of the anti-anxiety, muscle-relaxant, and anti-seizure activity that benzodiazepines have. That selectivity is the idea behind this class of medication, though it doesn't make these drugs free of risk.
What to expect
Eszopiclone works the same night. There is no weeks-long wait, because the sedating effect is immediate. Most people feel it within about 30 minutes, which is why it should be taken right before getting into bed.
Eszopiclone is longer-acting than the other z-drugs, with a half-life of roughly 6 hours. That longer action is what helps with staying asleep through the night, but it also makes next-morning grogginess more likely, so the dose matters. It can affect driving the next morning even when a person feels fine. A lower dose and a full night of sleep, about 7 to 8 hours, both reduce that risk.
Common side effects
Most people tolerate eszopiclone reasonably well, but side effects do happen. The common ones include:
- An unpleasant taste, often described as bitter or metallic, which can linger into the next day.
- Drowsiness.
- Dizziness.
- Dry mouth.
- Headache.
- Next-day grogginess.
The bitter taste is a well-known quirk of this medication and is harmless, though some people find it bothersome enough to switch. Next-day grogginess is often a sign the dose is higher than that person needs. If a side effect is severe, or it isn't improving, that's a conversation to have with the prescriber rather than a reason to stop on your own.
Serious side effects and warnings
Serious problems are uncommon, but a few are worth knowing.
Boxed warning. Eszopiclone carries an FDA boxed warning, the agency's strongest, about complex sleep behaviors. People have done things while not fully awake, such as sleepwalking, driving, preparing and eating food, making phone calls, or having sex, with no memory of it afterward. These episodes have caused serious injuries and deaths. The medication should be stopped, and not restarted, if a complex sleep behavior happens. Anyone who has ever had such an episode on eszopiclone or a similar drug should not take it.
- Next-day impairment. Because eszopiclone lasts longer than the other z-drugs, it is more likely to leave a person less alert the next morning and can affect driving even when they feel ready. Using the lowest effective dose helps limit this.
- Dependence, tolerance, and withdrawal. The risk is generally considered lower than with benzodiazepines, but it is real, especially with nightly use over long stretches.
- Allergic reactions. Severe allergic reactions are rare but can include swelling of the face, lips, or throat and need emergency care.
- Risk in older adults. Older adults are more sensitive to eszopiclone and face a higher risk of falls, confusion, and next-day impairment. It appears on the Beers list of medications to use with caution in older adults.
Sexual side effects
Eszopiclone does not cause the reduced sex drive or delayed orgasm linked to antidepressants. For people who want to avoid those effects, that is one less thing to weigh.
The one point worth noting is part of the boxed warning above. Complex sleep behaviors have, rarely, included sexual activity while a person is not fully awake and with no memory of it afterward. It is uncommon, but it is the reason this matters at all.
Weight, appetite, and sleep
Eszopiclone is essentially weight-neutral. It does not tend to change appetite or body weight the way some psychiatric medications do.
Its whole purpose is sleep. It is taken right before bed, only when a full night of sleep is possible, and the sedating effect is what it is meant to do. Eszopiclone is one of the few sleep medications studied in trials lasting up to six months, though short-term or intermittent use is still the usual approach.
Starting and dosing basics
This section is general background, not a dosing instruction for any individual. The right dose is a decision for a prescriber.
Eszopiclone comes as tablets. It is taken right before getting into bed, only when about 7 to 8 hours of sleep are possible. Because the longer action makes next-morning grogginess more likely, the dose matters, and lower doses are often used, especially for older adults. The prescriber sets the dose and adjusts it based on how a person responds.
Missed doses and interactions
Eszopiclone is a bedtime-only medication, so there is no "missed dose" to make up. If a night goes by without it, it is simply not taken. It should never be taken without a full night of sleep ahead, and it should not be taken in the middle of the night, because its longer action would carry well into the next day.
A few interactions matter. Alcohol and other sedating drugs add to eszopiclone's effect and its risks and should be avoided around it. Combining it with opioids is dangerous and can slow breathing. Give every prescriber and pharmacist a full list of your medications and supplements, including over-the-counter ones.
Stopping and tapering
Eszopiclone is a controlled substance, and the body can adjust to it with regular use. The dependence risk is generally lower than with benzodiazepines, but it is real, especially after nightly use over a long period.
Stopping after regular use can cause rebound insomnia, meaning a few nights of sleep that feel worse than before treatment. This usually settles within a short time. After longer or nightly use, a prescriber may suggest stepping the dose down gradually rather than stopping all at once. Deciding to stop is reasonable, but it is worth doing with guidance.
Pregnancy and breastfeeding
This is an area where individual circumstances matter and the decision belongs with a clinician. Poor sleep carries its own burden, and eszopiclone also passes into breast milk, with limited data on its effects. None of that adds up to one answer that fits everyone. Anyone who is pregnant, planning a pregnancy, or breastfeeding should talk it through with their prescriber so the specific risks and benefits can be weighed for their situation.
Cost and generic availability
Eszopiclone has been available as a generic for many years and is inexpensive. The brand name Lunesta costs more, but generic eszopiclone contains the same active medication and works the same way. Most insurance plans cover the generic, and for people paying out of pocket it is among the lower-cost sleep medications.
Common questions
Why does eszopiclone leave a bad taste? A bitter or metallic aftertaste is a known quirk of this medication, and it can linger into the next day. It is harmless, but some people find it bothersome enough to ask about a different option.
How is it different from other z-drugs? Eszopiclone lasts longer, with a half-life of about 6 hours. That helps with staying asleep through the night, but it also makes next-morning grogginess more likely than with shorter-acting z-drugs.
Is eszopiclone addictive? It is a Schedule IV controlled substance and can lead to dependence, though the risk is generally considered lower than with benzodiazepines. The risk is highest with nightly use over long periods.
Can I drive the morning after taking it? Eszopiclone can affect driving the next morning even when a person feels fine, and its longer action makes this more of a concern. A lower dose and a full night of sleep reduce the risk, but anyone unsure should be cautious and ask their prescriber.
How long can I take it? Eszopiclone has been studied in trials up to six months, but short-term or intermittent use is still the usual approach. For ongoing insomnia, cognitive behavioral therapy for insomnia (CBT-I) is the recommended first-line treatment.
Questions to ask your prescriber
- Is eszopiclone the right choice for me, or would CBT-I be a better starting point?
- How many nights a week should I take it, and for how long overall?
- What dose is right for me, and could next-day grogginess mean it is too high?
- Is it safe with the other medications and supplements I take?
- If we decide to stop it later, how would we do that safely?
Sources
This guide draws on current prescribing information and public health references. It is reviewed for clinical accuracy and updated as guidance changes.
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