Sonnat

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Sonnat

Method of action: Hypnotic

Treatment option: Insomnia

Medically reviewed

Laura Arias

Last updated on 22/12/2025

This page provides general, reference-level information compiled from official medical sources. It is not a substitute for professional medical advice, diagnosis, or treatment. For decisions about your health, please consult a qualified healthcare professional.

Overview of Sonnat

Property Description
Active ingredient Zopiclone
Form Oral Tablets (Film-coated)
Pharmacological class Sedative-Hypnotic
Common use Short-term management of Insomnia
Origin Synthetic cdot Non-benzodiazepine

What Type of Medicine is Sonnat (Zopiclone)?

Sonnat is a sedative-hypnotic medication, the primary function of which is the short-term treatment of severe insomnia and related sleep disorders when sleep initiation or maintenance is significantly impaired. The active ingredient is Zopiclone (INN), a synthetic compound that is clinically recognized and categorized as a Z-drug, which is a type of non-benzodiazepine hypnotic. This classification confirms that the medicine is primarily used to help facilitate the onset of sleep in adults facing debilitating rest difficulties. The pharmacological class of cyclopyrrolone derivative clearly distinguishes Zopiclone chemically from older classes, a differentiation supported by pharmacological studies that confirm its selective binding profile.

Composition and Physical Form of Sonnat

The medication's composition centers on the single-ingredient product, Zopiclone, which is designed for delivery via the oral route typically in the form of film-coated tablets. Zopiclone is a racemic mixture containing both active and inactive enantiomers. The substance works by acting as a positive allosteric modulator on the GABAA receptor in the Central Nervous System (CNS), a fundamental mechanism that enhances the effect of the inhibitory neurotransmitter GABA. This selective enhancement of natural calming processes is key to the drug's action, utilizing pharmaceutical excipients to ensure the controlled delivery of the active substance within the solid tablet form. This makes Sonnat suitable for a target patient group requiring prompt and temporary pharmacological aid for sleep issues.

What side effects are possible with Sonnat?

Possible side effects and safety information

The official safety profile for Sonnat (Zopiclone) is defined by frequency classifications and physiological system groupings documented in regulatory prescribing information. The most Common adverse reactions, occurring in more than 1 in 100 people, include dysgeusia (a persistent bitter or metallic taste), somnolence, dizziness, headache, and dry mouth.


Documented Safety Patterns and Serious Adverse Reactions

Adverse effects are grouped by System-Organ Class (SOC), prominently featuring Nervous System Disorders (e.g., somnolence, amnesia) and Gastrointestinal Disorders (e.g., nausea, dry mouth). Uncommon effects include fatigue, nightmares, and agitation, while Rare effects include anterograde amnesia, confusion, and aggression.

Serious adverse reactions officially documented include rare but severe anaphylactic reactions and angioedema (swelling that may compromise the airway). Regulatory documents also emphasize the risk of complex sleep behaviors, such as sleep-walking or sleep-driving, which are often accompanied by amnesia for the event.


Population-Specific Constraints and Duration Risk

Specific safety considerations apply to certain populations. Zopiclone is contraindicated in individuals with severe hepatic insufficiency or severe impairment of respiratory function, and in the pediatric population (under 18 years). Older adults may have an increased sensitivity to effects, leading to a higher risk of falls.

Use is intended for the short term, as the risk of developing physical and psychological dependence and withdrawal syndrome increases with the duration of treatment, particularly when exceeding four weeks. Rebound insomnia (worsening of sleep upon cessation) is a documented risk associated with abrupt discontinuation.

Overdose and Emergency Response

The official regulatory profile for Sonnat overdose defines the manifestations as a spectrum of dose-dependent Central Nervous System (CNS) depression. Overdose presentations range from excessive somnolence, confusion, and ataxia (loss of coordination) to severe coma. Physiologically, the CNS, respiratory, and cardiovascular systems may be affected, with documented signs including hypotonia (floppy muscles) and shallow breathing due to respiratory depression.

The risk of a life-threatening outcome, including death, is significantly increased in cases of co-ingestion with other CNS depressants, such as alcohol or opioids, which is a primary concern noted in official warnings across regulatory documents. Elderly patients are also noted to be at an increased risk of adverse outcomes and severity.

Immediate medical attention is required whenever an overdose is suspected, even if symptoms are not fully apparent, or if severe signs such as difficulty breathing or loss of consciousness occur; regulators mandate contacting emergency services immediately. Clinical management is primarily symptomatic and supportive, focused on maintaining vital signs and a patent airway. While Flumazenil, a competitive antagonist, is noted as a procedural option that may be used to reverse CNS effects, its administration requires careful clinical assessment.

Therapeutic Uses of Sonnat

What Sonnat Treats: Main Uses and Benefits

Sonnat (Zopiclone) is used in areas where short-term symptom management is appropriate for impaired rest. It is applied across domains where additional symptomatic support is needed. This medication is commonly used for the short-term treatment of severe insomnia in adults and older adults.


Sonnat is relevant in clinical settings that involve acute or unstable symptom patterns. It is commonly used across conditions presenting with acute episodes, such as difficulty falling asleep, frequent nocturnal awakenings, and waking too early. It is generally used when short-term symptomatic assistance is needed to address symptoms that create noticeable physiological strain. It provides support that helps ease the overall symptom burden.

“This medication is applied during phases when sleep symptoms become temporarily overwhelming, supporting general well-being during symptomatic periods.”

Quick Fact: Relief for Sleep Continuity Disturbances

This medicine assists with managing symptom clusters that may appear suddenly or fluctuate. It helps address symptom clusters that may become intense or disruptive in situations where functional stability becomes affected.

Eligibility and Restrictions for Use

Eligibility Profile: Who Can and Cannot Use Sonnat (Zopiclone)

Official regulatory documents define strict criteria for using Sonnat, which contains the active ingredient Zopiclone. Use is generally permitted for adults (18 years and older) who require short-term treatment for insomnia.


Absolute Contraindications (Must Not Use)

The medicine is contraindicated and must not be used by patients with the following severe conditions or characteristics:

  • Known hypersensitivity to zopiclone or excipients.
  • Myasthenia Gravis (severe muscle weakness).
  • Severe Hepatic Insufficiency (severe liver failure).
  • Severe Sleep Apnoea Syndrome or Respiratory Failure.
  • A history of complex sleep behaviors after taking zopiclone.
  • Children and adolescents under 18 years (use not established).

Populations with Restricted or Conditional Use

Treatment must proceed with caution or at a reduced initial dose for certain populations, including older adults (geriatric patients), and patients with impaired renal function, non-severe hepatic insufficiency, or chronic respiratory insufficiency. Additionally, use is not recommended for women who are pregnant or breastfeeding.

What should I know about interactions with other medicines?

The official interaction profile of Sonnat (Zopiclone) is defined by two primary regulatory domains: pharmacokinetic alteration and pharmacodynamic potentiation. Pharmacodynamic interaction occurs when Sonnat is co-administered with other Central Nervous System (CNS) depressants, including opioids, antipsychotics, anxiolytics, and sedative antihistamines. This combination is documented to produce additive CNS depressant effects, increasing the risk of profound sedation and respiratory depression. Regulatory information advises that the concomitant use of Opioids must be strictly reserved for patients lacking adequate alternative options.

Pharmacokinetic interactions are determined by substances affecting the CYP3A4 metabolic pathway, the major isoenzyme involved in clearance. Potent CYP3A4 inhibitors (such as Ketoconazole or Erythromycin) increase the exposure and plasma concentration of Zopiclone, which can enhance its hypnotic effect. Conversely, inducers like Rifampicin and the herbal product St. John's Wort may reduce concentrations, leading to diminished efficacy.

Substance-specific restrictions include the prohibition of Alcohol, which potentiates the sedative effect and increases the risk of serious adverse outcomes. Additionally, the label notes that consuming a high-fat/heavy meal with the tablet may delay the time to peak concentration. A critical timing constraint is documented: patients face an increased risk of next-day psychomotor impairment if fewer than seven to twelve hours are allowed between administration and activities requiring complete mental alertness.

Mechanism of Action

Sonnat (Zaleplon) functions as a positive allosteric modulator that interacts with the GABA A receptor complex, primarily in the central nervous system. The compound targets the benzodiazepine (BZ) binding site, located at the alpha and gamma subunit interface, demonstrating a relative selectivity for alpha1-containing GABA A receptor subtypes.

Binding of Sonnat to the BZ site does not directly activate the receptor but potentiates the inhibitory effects of the endogenous neurotransmitter gamma-aminobutyric acid (GABA). This potentiation increases the frequency of chloride channel opening within the receptor complex. The resulting increased influx of Cl^- ions leads to hyperpolarization of the postsynaptic neuron membrane.

This sustained hyperpolarization decreases neuronal excitability and reduces the firing rate of central neurons. The overall system-level consequence is a pervasive, non-selective central nervous system (CNS) depression, characterized by decreased latency to sleep onset.

Dosage and Administration Information

How to Use Sonnat: Administration Guidelines

Sonnat (zaleplon) is taken orally. The use of this medicine is characterized by strict timing and defined dose limits to structure correct administration.


Administration Requirements

Usage Domain Administration Rule
Route of Administration Oral (by mouth) capsule.
Timing & Frequency Take immediately before going to bed OR after going to bed and experiencing difficulty falling asleep. Never take a second dose within a single night.
Fasting Condition Should not be taken with or immediately after a heavy, high-fat meal, as this may reduce its effect.
Duration of Use Treatment should be as short as possible and generally should not exceed two weeks without re-evaluation.

Dosing Rules

Patient Group Recommended Daily Dose Maximum Daily Dose Special Condition Rule
Non-Elderly Adults 10 mg 20 mg Should have at least 4 hours of uninterrupted sleep remaining.
Elderly Patients 5 mg 10 mg Dosing is reduced due to potential sensitivity to the drug's effects.
Mild to Moderate Liver Impairment 5 mg 10 mg Lower dose is required as clearance is reduced in this population.

These parameters establish the standardized protocol for Sonnat use: it is administered once nightly to facilitate sleep onset, with precise adjustments to the starting and maximum dose for elderly patients or those with mild to moderate liver impairment. The limitations on the timing of administration relative to sleep and food are essential procedural steps.

Recent Clinical Evidence

Research Evidence / Overview of Studies for Sonnat (Zopiclone)


Evidence for Short-Term Treatment of Severe Insomnia

Research exploring the use of Sonnat for severe insomnia primarily involves short-term Randomized Controlled Trials (RCTs) and comprehensive literature reviews. These studies were applied in research contexts involving fluctuating or unstable symptoms of insomnia in adults. Researchers monitored objective and subjective outcomes related to sleep initiation (time taken to fall asleep) and sleep maintenance (duration of nocturnal awakenings).

The RCTs explored the difference between Zopiclone and a placebo (a sugar pill) over defined time intervals, usually for only a few weeks (e.g., 2 to 4 weeks). Studies report how symptoms evolved in the observed populations, and studies report measurements of specific changes in the time taken to fall asleep. Evidence helps contextualize symptom patterns. Findings sometimes vary across studies, which includes instances of comparing self-reported data from patients with objective measurements gathered in a sleep lab setting.


Studies Focused on Acute Sleep Disturbances

Research has also explored the temporary use of Sonnat during acute or disruptive episodes of sleep loss, such as when individuals experience sudden, severe difficulty falling asleep. These studies were relevant in trials assessing short-term or episodic symptom patterns. Research examined outcomes related to physical discomfort and outcomes reflecting daily functioning or activity level. Studies focusing on episodes where symptoms become more noticeable report on short-term changes in specific sleep metrics like how quickly sleep onset occurs and the duration of nocturnal awakenings over a short observation period. Research contributes to the broader evidence landscape of short-term changes. Studies exploring repeated, intermittent acute use are limited.


Evidence in Special Populations

Studies monitored the use of Zopiclone in specific patient cohorts, most notably Older Adults (individuals aged 65 and over). Research examined older adults who presented with chronic insomnia. Furthermore, some studies have explored the use of Zopiclone in individuals with comorbid conditions, such as those with insomnia associated with advanced cancer, conducting short-term trials to monitor outcomes describing episodic or acute changes. The research describes patterns observed in these specific populations; however, findings for different subgroups remain limited, and data for certain groups remain insufficient.


Long-Term Studies and Follow-up Data

The available evidence for Sonnat was studied for use over short durations, typically not exceeding four weeks. The medication was studied for short-term symptom changes, reflecting the defined duration of use. Data show patterns related to the observed changes during these defined, brief periods. However, there is limited information for long-term outcomes and studies that follow patients for many months or years are scarce. Therefore, the long-term effects of using Sonnat are not well characterized. Research has explored how patients reported their experience after the drug was stopped, but continuous follow-up durations were limited in most of the existing trial data.


What is Still Uncertain About Sonnat Research

The existing research still has several gaps and areas of uncertainty. There is limited information for long-term outcomes, as research largely focused on the short-term use of four weeks or less. Consequently, certainty remains low regarding the research outcomes of extended use. Furthermore, comparative evidence between Zopiclone and other treatment options may be mixed or lacking in high-quality studies. Subgroup findings are uncertain for many specific populations beyond the general adult cohort and older adults. Ultimately, while studies help show what has been observed so far under controlled conditions, the results apply only to the populations studied, and research does not determine whether an individual will respond similarly outside of those study parameters.

Frequently Asked Questions (FAQ)

Common questions about Sonnat (FAQ)

Q: How quickly should a person expect to notice the effects of Sonnat?

Official product information indicates that Sonnat is quickly absorbed by the body. A person typically reaches the highest level of the medicine in their blood about one hour after administration. This rapid absorption pattern is why the medicine is usually taken right before going to bed.

Q: Is it necessary to finish the entire course of Sonnat, even if I feel better?

The official instructions state that the use of this medicine should be as short as possible and generally should not exceed two to four weeks. Using it for longer than this duration increases the risk of dependence and withdrawal symptoms. Regulatory information indicates that abrupt discontinuation carries the risk of withdrawal symptoms and rebound insomnia.

Q: Does Sonnat cause changes in weight (gain or loss)?

According to official product labeling and safety documentation, changes in body weight are not listed among the expected or common side effects of Sonnat.

Q: How long does Sonnat stay in the body after the last use?

Regulatory documents describe how the active ingredient in Sonnat is eliminated from the body. For non-elderly adults, the medicine has an average half-life of approximately six hours. This indicates the rate at which half of the medicine is cleared from the bloodstream in that time.

Q: Do I need a special blood test or monitoring while using Sonnat?

Health authority documents state that certain blood tests may be required during treatment with Sonnat. Official information also notes that patients are typically monitored routinely for signs of misuse and abuse.

Q: Can Sonnat affect the results of routine lab tests?

Yes, regulatory documents indicate that the medicine has the potential to cause abnormal results in certain routine laboratory tests.

Q: What is the difference between an 'interaction' and a 'contraindication' for Sonnat?

An interaction describes a change in Sonnat's effect when another food, drink, or medicine is present in the body. A contraindication, according to official documents, is a specific condition (such as severe liver disease) that completely prohibits the use of the medicine because the risks are too high.

Q: Why does the official literature mention specific populations who cannot use Sonnat?

Official literature highlights specific populations who cannot use Sonnat (contraindications) to prevent serious harm. This emphasis is necessary to mitigate the risk of severe adverse effects, such as complications from pre-existing severe respiratory or liver conditions.

Q: If someone is lactose intolerant, can they still use Sonnat tablets?

The tablets contain lactose monohydrate. Because of this, official documents note that individuals with rare hereditary issues like galactose intolerance or total lactase deficiency may not be suitable candidates for this medicine.

Q: Is Sonnat affected by grapefruit or grapefruit juice?

Regulatory information notes that Sonnat is processed by a specific liver enzyme pathway, CYP3A4. Strong inhibitors of this pathway, which includes compounds found in grapefruit, are warned against in official sources because they can affect the medicine's levels in the body.

Q: If I have a history of heart problems, can I still be eligible for Sonnat?

The official contraindication list for Sonnat primarily focuses on severe respiratory issues, severe liver insufficiency, and muscle weakness (Myasthenia Gravis). A history of heart problems or cardiac issues is not listed in the official documents as an absolute contraindication for use.

Q: Can Sonnat affect sleep patterns?

Sonnat is intended to help a person initiate and sustain sleep. However, official information also notes that documented effects include potential disturbances like nightmares, amnesia, and complex sleep behaviors such as sleepwalking or sleep-driving.

Q: What types of food or drink interact with Sonnat?

Regulatory warnings emphasize that alcohol should be avoided during the use of this medicine. Official instructions also note that taking Sonnat with or immediately following a heavy, high-fat meal may reduce its intended effect.

Q: Is there a list of vitamins or supplements that should not be taken with Sonnat?

Official regulatory documents specifically warn against the use of the herbal product St. John's Wort. Using this supplement is discouraged because it can decrease the effectiveness of Sonnat.

Q: Can Sonnat be safely used by older adults (e.g., over 65)?

Official dosing guidelines indicate that older adults typically require a lower initial dose and a lower maximum dose. This adjustment is necessary because older adults may have increased sensitivity and a slightly prolonged rate of drug elimination.

Q: What is the current official safety classification of Sonnat (e.g., Pregnancy Category)?

Official sources describe the use of this medicine during pregnancy as generally not recommended. Use, particularly in the later stages of pregnancy, is noted to potentially increase the chance of withdrawal symptoms in the newborn.

Q: If I miss a scheduled time to use Sonnat, what general guidance is provided?

Official guidance describes a protocol where a missed dose is generally skipped, with use resuming at the next scheduled time. Regulatory information stresses that taking multiple doses or a dose at an inappropriate time should be avoided.

Q: What does the term 'contraindication' mean in relation to Sonnat?

In official documents, a contraindication is a specific condition or factor that serves as a reason to withhold a medical treatment because the risk would clearly outweigh any possible benefit.

Q: How does Sonnat affect the liver or kidneys?

Sonnat is primarily processed and eliminated from the body by the liver and kidneys. Official documents note that dose adjustments may be necessary for patients with pre-existing mild to moderate impairment in the function of these organs.

Q: Does taking Sonnat require any specific lifestyle changes?

Official warnings specify the need for complete avoidance of alcohol during the use of Sonnat. Additionally, a window of seven to twelve hours must be allowed between taking the dose and engaging in activities that require full mental alertness, such as driving.

Q: What is the likelihood of developing an allergic reaction to Sonnat?

The official safety profile classifies the most serious allergic reactions, such as anaphylaxis (a severe whole-body reaction) and angioedema (swelling), as rare or very rare events. Rare means they occur in up to 1 in 1,000 people.

Q: What specific warnings are highlighted in the official documents for Sonnat?

Official documents highlight several key warnings, including the risk of dependence and withdrawal with prolonged use. Other major warnings involve the potential for complex sleep behaviors, such as sleepwalking, and the risk of increased central nervous system depression when combined with substances like opioids or alcohol.

Q: How is the purpose of Sonnat described in patient-friendly terms?

In patient-friendly language, Sonnat is described as a type of sleeping pill. Its purpose is the short-term treatment of severe insomnia, specifically to help users fall asleep more quickly when their sleep initiation is significantly impaired.

Q: What is the difference in how Sonnat works compared to older treatments for the same condition?

Sonnat belongs to the Z-drug class, which is chemically distinct from older benzodiazepine treatments. Official information states that its action involves binding to a different location on the GABAA receptor complex, giving it a different pharmacological profile compared to older treatments.

How should Sonnat be stored and disposed of?

How to Store and Dispose of Sonnat (Zopiclone)

Regulatory documents define specific storage and disposal requirements to ensure product integrity and safety.


Storage and Handling Requirements

Condition Requirement (Official Labeling)
Temperature Store below 30 C (e.g., Controlled Room Temperature).
Protection Must be kept in a cool, dry place. Protect from light and moisture.
Packaging Must be kept in the original container or package.
Child Safety Keep this medicine out of the sight and reach of children.

Product Stability and Disposal

Do not use the tablets after the expiry date printed on the packaging. The disposal of Sonnat must follow official guidelines. Do not throw away unused or expired tablets via wastewater or general household waste. Instead, regulatory instructions specify to return any unused medicine to a pharmacist to ensure proper disposal in accordance with local environmental requirements.

Attention! Always consult to a doctor or pharmacist before using pills or medicines.

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