Last reviewed 2026-04-20 · How we verify

Lunesta (ESZOPICLONE)

Lunesta works by enhancing the activity of a neurotransmitter called GABA, which helps calm the brain and promote sleep.

Lunesta (eszopiclone) is a small molecule drug developed by Sunovion Pharm Inc and currently owned by Waylis Therap. It targets the gamma-aminobutyric acid receptor subunit alpha-1 to treat insomnia. Lunesta was FDA-approved in 2004 and is now off-patent with 14 generic manufacturers. As a non-benzodiazepine hypnotic, Lunesta is used to help individuals fall asleep and stay asleep. Its commercial status allows for generic competition, making it more accessible to patients.

At a glance

Mechanism of action

Mechanism of action. The precise mechanism of action of eszopiclone as hypnotic is unknown, but its effect is believed to result from its interaction with GABA-receptor complexes at binding domains located close to or allosterically coupled to benzodiazepine receptors. Eszopiclone is nonbenzodiazepine hypnotic that is pyrrolopyrazine derivative of the cyclopyrrolone class with chemical structure unrelated to pyrazolopyrimidines, imidazopyridines, benzodiazepines, barbiturates, or other drugs with known hypnotic properties.

Approved indications

• Insomnia

Boxed warnings

• WARNING: COMPLEX SLEEP BEHAVIORS WARNING: COMPLEX SLEEP BEHAVIORS Complex sleep behaviors including sleep-walking, sleep-driving, and engaging in other activities while not fully awake may occur following use of eszopiclone tablets. Some of these events may result in serious injuries, including death. Discontinue eszopiclone tablets immediately if a patient experiences a complex sleep behavior [see Contraindications (4) and Warnings and Precautions (5.1) ]. WARNING: COMPLEX SLEEP BEHAVIOUR See full prescribing information for complete boxed warning. Complex sleep behaviors including sleep-walking, sleep-driving, and engaging in other activities while not fully awake may occur following use of eszopiclone tablets. Some of these events may result in serious injuries, including death. Discontinue eszopiclone tablets immediately if a patient experiences a complex sleep behavior ( 4 , 5.1 ).

Common side effects

• Somnolence
• Viral Infection
• Dry Mouth
• Dyspepsia
• Nausea
• Dizziness
• Pain
• Diarrhea
• Headache
• Unpleasant Taste
• Accidental Injury
• Dysmenorrhea

Drug interactions

• itraconazole
• ketoconazole
• nefazodone
• nelfinavir
• rifampicin
• ritonavir
• troleandomycin

Key clinical trials

• National Adaptive Trial for PTSD Related Insomnia (PHASE3)
• Continuous Positive Airway Pressure, Arousability and Links to Mechanisms in Obstructive Sleep Apnea (PHASE3)
• Endotype-Targeted Therapy to Rescue OSA Patients Struggling With CPAP Adherence (TOP-CPAP) (PHASE2)
• Effectiveness of Combining Behavioral and Pharmacologic Therapy for Complex Insomnia in Veterans With PTSD (PHASE4)
• Endotypic Traits and Obstructive Sleep Apnea Surgery (PHASE2)
• Impact of Eszopiclone on Blood Pressure in Patients With Insomnia and Hypertension (PRYSMA-HTN) (PHASE4)
• Grain Moxibustion Treatment on Insomnia: a Randomized Controlled Trial (NA)
• The Study in Outpatient Medicine Using Nudges to Improve Sleep (NA)

Primary sources

Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.

Competitive intelligence

For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:

• Lunesta CI brief — competitive landscape report
• Lunesta updates RSS · CI watch RSS
• Waylis portfolio CI