Zolpidem: Uses, Dosage & Side Effects
A sedative-hypnotic medication for the short-term treatment of insomnia in adults
Zolpidem is a fast-acting, non-benzodiazepine sedative-hypnotic medication prescribed for the short-term treatment of insomnia in adults. It works by selectively binding to the GABA-A receptor to promote sleep onset, increase total sleep duration, and reduce nighttime awakenings. Treatment should be limited to 2–4 weeks due to the risk of tolerance and dependence. Zolpidem is available as 5 mg and 10 mg film-coated tablets under brand names including Stilnoct, Ambien, and various generics.
Quick Facts
Key Takeaways
- Zolpidem is a short-acting sleep medication intended for short-term use only (maximum 2–4 weeks) due to the risk of tolerance and dependence.
- Take it immediately before bedtime and only when you can sleep for at least 7–8 uninterrupted hours to avoid next-day impairment.
- Zolpidem can cause complex sleep behaviors such as sleepwalking, sleep-driving, and performing activities while not fully awake—stop the medication immediately if this occurs.
- Never combine zolpidem with alcohol, opioids, or other CNS depressants as this can cause life-threatening respiratory depression.
- Elderly patients and those with liver impairment should use a reduced starting dose of 5 mg.
What Is Zolpidem and What Is It Used For?
Quick Answer: Zolpidem is a prescription sedative-hypnotic that belongs to the non-benzodiazepine class of sleep medications. It is used for the short-term treatment of insomnia in adults, helping patients fall asleep faster and maintain sleep throughout the night.
Zolpidem is an imidazopyridine compound that acts as a selective agonist at the alpha-1 subunit of the GABA-A receptor complex in the brain. Unlike traditional benzodiazepines, which bind non-selectively to multiple GABA-A receptor subtypes, zolpidem's selective binding profile means it produces primarily sedative and hypnotic effects with comparatively less anxiolytic, muscle relaxant, and anticonvulsant activity. This selectivity contributes to its favorable side effect profile as a sleep aid.
The primary indication for zolpidem is the short-term management of insomnia characterized by difficulty falling asleep (sleep-onset insomnia). Clinical studies have demonstrated that zolpidem significantly reduces sleep latency—the time it takes to fall asleep—and increases total sleep time. It typically begins working within 15 to 30 minutes of oral administration and has a short elimination half-life of approximately 2.5 hours, which minimizes the risk of residual next-day sedation when used at recommended doses.
Zolpidem treatment should always be as short as possible. International guidelines recommend limiting treatment to a maximum of 2–4 weeks, including the tapering period. This is because prolonged use can lead to the development of tolerance (where higher doses are needed to achieve the same effect) and physical dependence. If insomnia symptoms persist beyond 7–14 days of treatment, patients should consult their healthcare provider to investigate underlying causes of sleep disturbance, such as sleep apnea, chronic pain, depression, or other medical conditions.
Zolpidem is available under numerous brand names worldwide, including Stilnoct, Ambien (in the United States), Zolpidem Sandoz, Zolpidem HEXAL, Zolpidem STADA, Zolpidem Orifarm, Zolpidem Vitabalans, and Zolpidem Forza, among many generic formulations. All these products contain the same active ingredient—zolpidem tartrate—and are therapeutically equivalent when used at the same dose. The medicine is classified under ATC code N05CF02 and is a controlled or prescription-only substance in virtually all countries.
What Should You Know Before Taking Zolpidem?
Quick Answer: Before taking zolpidem, inform your doctor about any history of substance abuse, liver or kidney disease, respiratory problems, mental health conditions, or if you are pregnant or breastfeeding. Zolpidem is contraindicated in patients with severe liver impairment, severe respiratory insufficiency, sleep apnea, and myasthenia gravis.
Contraindications
Zolpidem must not be used if any of the following conditions apply:
- Allergy to zolpidem tartrate or any of the excipients in the formulation (including lactose monohydrate, microcrystalline cellulose, and magnesium stearate).
- Severe hepatic impairment — zolpidem is extensively metabolized by the liver, and impaired hepatic function can lead to dangerous drug accumulation.
- Severe respiratory insufficiency — zolpidem can further depress respiratory drive, potentially leading to life-threatening respiratory failure.
- Obstructive sleep apnea syndrome — the sedative effects of zolpidem can worsen apneic episodes and oxygen desaturation during sleep.
- Myasthenia gravis — this neuromuscular condition may be exacerbated by the muscle-relaxant properties of zolpidem.
- History of complex sleep behaviors — if you have previously experienced sleepwalking or other unusual sleep behaviors (such as sleep-driving, sleep-eating, making phone calls, or having sexual intercourse while not fully awake) after taking zolpidem or any other Z-drug.
Warnings and Precautions
Before starting zolpidem, discuss the following with your healthcare provider:
Zolpidem can cause patients to perform activities while not fully awake, including sleepwalking, sleep-driving, preparing and eating food, making phone calls, and engaging in sexual activity, with no memory of these events the following morning. These behaviors can lead to serious injury or death. If you experience any such behavior, stop taking zolpidem immediately and contact your doctor. Consuming alcohol or other CNS depressants with zolpidem significantly increases this risk.
Tolerance and dependence: Continued use of zolpidem beyond several weeks can result in tolerance, where the sleep-inducing effect diminishes over time. Physical and psychological dependence can develop, particularly with doses exceeding the recommended maximum, treatment durations longer than 4 weeks, and in patients with a history of alcohol, drug, or medication abuse. Healthcare providers should carefully assess the risk-benefit balance in these populations.
Rebound insomnia: When zolpidem treatment is discontinued abruptly, a transient rebound effect may occur in which insomnia symptoms return in a more severe form than before treatment. This can be accompanied by mood changes, anxiety, and restlessness. To minimize rebound effects, the dose should be gradually reduced under medical supervision rather than stopped suddenly.
Amnesia: Anterograde amnesia (difficulty forming new memories) can occur, typically several hours after taking zolpidem. To reduce this risk, patients must ensure they can dedicate at least 8 hours to uninterrupted sleep after taking the medication.
Psychiatric and paradoxical reactions: In some patients, particularly the elderly, zolpidem can paradoxically cause restlessness, agitation, irritability, aggression, delusions, rage, nightmares, hallucinations, delirium, and inappropriate behavior. If any of these reactions occur, zolpidem should be discontinued immediately.
Fall risk: Zolpidem causes drowsiness and can impair coordination and balance, particularly in elderly patients. This increases the risk of falls and associated injuries such as hip fractures, especially if patients get up during the night after taking the medication.
Next-day impairment: The risk of impaired coordination, including impaired driving ability, is increased the day after taking zolpidem if: the dose was taken less than 8 hours before activities requiring alertness; a dose higher than recommended was taken; zolpidem was taken with other CNS depressants, alcohol, or illicit drugs. The FDA and EMA have issued specific warnings about next-day driving impairment with zolpidem.
Suicidal ideation: Some studies have reported an increased risk of suicidal thoughts, suicide attempts, and completed suicide in patients taking certain sedative-hypnotic medications, including zolpidem. While a causal relationship has not been definitively established, patients with depressive symptoms or suicidal ideation should be closely monitored and should seek immediate medical attention if such thoughts occur.
Zolpidem must not be used in children and adolescents under 18 years of age. Safety and efficacy have not been established in this population.
Pregnancy and Breastfeeding
Pregnancy: Zolpidem is not recommended during pregnancy. Some studies have suggested a possible increased risk of cleft lip and cleft palate in newborns exposed to zolpidem during the first trimester. Use during the last six months of pregnancy may cause reduced fetal movements and changes in fetal heart rate. If taken late in pregnancy or during labor, the newborn may experience muscle weakness, low body temperature, feeding difficulties, and respiratory depression. Regular use in late pregnancy can cause physical dependence in the infant, with a risk of withdrawal symptoms (agitation, tremors) after birth that require neonatal monitoring.
Breastfeeding: Small amounts of zolpidem are excreted into breast milk. As the effects on the nursing infant have not been sufficiently studied, zolpidem should not be used while breastfeeding. If you are breastfeeding, consult your doctor for advice on alternative approaches to managing insomnia.
Driving and Operating Machinery
Zolpidem significantly impairs the ability to drive and operate machinery. The day after taking zolpidem, patients should be aware that they may experience drowsiness, dizziness, confusion, double or blurred vision, and slowed reaction times. International regulatory agencies recommend a minimum interval of 8 hours between taking zolpidem and driving, operating machinery, or working at heights. Alcohol and other psychoactive substances must be avoided while taking zolpidem, as they potentiate these impairing effects.
How Does Zolpidem Interact with Other Drugs?
Quick Answer: Zolpidem interacts with many medications, especially other CNS depressants. Combining zolpidem with opioids, benzodiazepines, antipsychotics, sedating antihistamines, or alcohol can lead to severe drowsiness, respiratory depression, coma, and death. Always inform your doctor about all medications you are taking.
Drug interactions with zolpidem can be broadly divided into two categories: pharmacodynamic interactions (where the combined effect on the body is altered) and pharmacokinetic interactions (where one drug affects the blood levels of another). Understanding these interactions is critical for patient safety, as many can be life-threatening.
Major Interactions (Avoid Combination)
Concurrent use of zolpidem with opioid analgesics (such as morphine, oxycodone, fentanyl, tramadol, or codeine), opioid substitution therapy, or opioid-containing cough medications significantly increases the risk of profound sedation, respiratory depression, coma, and death. This combination should only be considered when no other treatment alternatives exist, and doses should be minimized by the prescribing physician.
| Drug / Class | Interaction Effect | Risk Level |
|---|---|---|
| Opioid analgesics (morphine, oxycodone, fentanyl, codeine, tramadol) | Severe respiratory depression, profound sedation, coma, death | Avoid — life-threatening |
| Benzodiazepines (diazepam, lorazepam, alprazolam) | Enhanced sedation, respiratory depression, increased fall risk | Avoid combination |
| Alcohol | Markedly enhanced sedation, complex sleep behaviors, memory impairment | Contraindicated |
| Antipsychotics (quetiapine, olanzapine, haloperidol) | Increased drowsiness, impaired coordination, fall risk | Avoid or use with caution |
| Sedating antihistamines (diphenhydramine, hydroxyzine, promethazine) | Additive sedation, next-day drowsiness, cognitive impairment | Avoid combination |
| Fluvoxamine | Significantly increases zolpidem blood levels via CYP1A2 inhibition | Not recommended |
| Ciprofloxacin | Increases zolpidem blood levels via CYP1A2 inhibition | Not recommended |
Moderate Interactions (Use with Caution)
The following medications may interact with zolpidem and require dose adjustment or careful monitoring:
| Drug / Class | Interaction Effect | Clinical Advice |
|---|---|---|
| SSRIs/SNRIs (fluoxetine, sertralin, venlafaxine, bupropion) | Hallucinations reported; increased CNS depression | Monitor closely; report hallucinations |
| Anticonvulsants (carbamazepine, phenytoin, valproate) | Additive CNS depression; some may reduce zolpidem levels | Dose adjustment may be needed |
| Ketoconazole (antifungal) | Increases zolpidem blood levels via CYP3A4 inhibition | Consider lower zolpidem dose |
| Rifampicin (anti-tuberculosis) | Significantly reduces zolpidem blood levels via CYP3A4 induction | Zolpidem may be less effective |
| St. John's Wort (herbal) | May reduce zolpidem effectiveness via CYP3A4 induction | Avoid concurrent use |
| General anesthetics | Enhanced and prolonged sedation | Inform anesthetist of zolpidem use |
Always tell your doctor, pharmacist, or anesthetist about all medications you are taking, including over-the-counter drugs, herbal supplements (especially St. John's Wort), and any recent alcohol consumption. It may also be helpful to inform close family members or friends about the risks described above, particularly regarding complex sleep behaviors.
What Is the Correct Dosage of Zolpidem?
Quick Answer: The standard adult dose is 10 mg taken once daily immediately before bedtime. Elderly patients and those with liver impairment should start with 5 mg. Never exceed 10 mg in any 24-hour period. Treatment should not exceed 4 weeks.
Zolpidem should always be taken exactly as prescribed by your doctor. It is designed as a single dose taken immediately before going to bed, and no additional dose should be taken during the same night. Patients must ensure at least 8 hours remain before any activity requiring full alertness.
Adults
Standard Adult Dose
Recommended dose: 10 mg once daily
When to take: Immediately before bedtime
Maximum dose: 10 mg per 24 hours
Important: Take as a single dose; do not take a second dose during the same night.
Some patients may be prescribed a lower starting dose of 5 mg based on their individual response, body weight, or other factors. The prescribing doctor will determine the appropriate dose. The 10 mg tablet is scored and can be divided into two equal halves.
Elderly Patients (Over 65 Years)
Elderly / Debilitated Patients
Recommended dose: 5 mg once daily
Rationale: Elderly patients are more sensitive to sedative effects and have slower drug metabolism, increasing the risk of falls, next-day drowsiness, and cognitive impairment.
Patients with Hepatic Impairment
Mild to Moderate Liver Impairment
Recommended starting dose: 5 mg once daily
Note: Zolpidem is contraindicated in patients with severe liver impairment due to the risk of drug accumulation and toxicity.
Children and Adolescents
Zolpidem is not approved for use in children and adolescents under 18 years of age. Safety and efficacy data are insufficient to support pediatric use. Alternative approaches to childhood insomnia should be discussed with a pediatric specialist.
Treatment Duration
Treatment with zolpidem should be as short as possible and should not exceed 4 weeks, including the gradual dose-reduction period. If sleep difficulties persist after 7–14 days of treatment, the patient should return to their doctor for reassessment, as the insomnia may have underlying causes that require different management.
| Patient Group | Recommended Dose | Maximum Duration | Special Notes |
|---|---|---|---|
| Adults (18–64 years) | 10 mg once daily | 4 weeks | Take immediately before bedtime |
| Elderly (≥65 years) | 5 mg once daily | 4 weeks | Increased sensitivity; higher fall risk |
| Mild-moderate hepatic impairment | 5 mg once daily | 4 weeks | Monitor for excessive sedation |
| Severe hepatic impairment | Contraindicated | N/A | Do not use |
| Children & adolescents (<18) | Not approved | N/A | Safety and efficacy not established |
Missed Dose
Do not take a double dose to compensate for a missed dose. If you forget to take zolpidem at bedtime but remember during the night, only take it if you still have at least 7–8 hours remaining for sleep. Otherwise, skip the missed dose and take your usual dose the following night at bedtime.
Overdose
If you suspect an overdose of zolpidem—whether in yourself, another adult, or a child who has accidentally ingested the medication—call your local emergency number or poison control center immediately. Zolpidem overdose can cause extreme drowsiness, confusion, impaired breathing, and loss of consciousness. The risk is substantially increased when zolpidem is taken with alcohol, opioids, or other sedating medications.
Stopping Treatment
Do not stop taking zolpidem suddenly without medical guidance, especially after regular use for more than a few days. Abrupt discontinuation can cause withdrawal symptoms including headache, muscle pain, anxiety, tension, restlessness, confusion, and irritability. In more severe cases, withdrawal may include tremor, sweating, and rebound insomnia. Your doctor will typically recommend gradually reducing the dose over several days to minimize these effects.
What Are the Side Effects of Zolpidem?
Quick Answer: Common side effects include drowsiness, dizziness, headache, and gastrointestinal disturbances. More serious but less common effects include hallucinations, complex sleep behaviors (sleepwalking, sleep-driving), memory impairment, and depression. Seek immediate medical attention if you experience facial swelling, difficulty breathing, or hives.
Like all medications, zolpidem can cause side effects, although not everyone experiences them. The frequency classifications below follow international pharmacovigilance standards. If you experience any concerning symptoms, contact your healthcare provider.
Stop taking zolpidem and call emergency services immediately if you develop swelling of the face, tongue, or throat; difficulty swallowing; hives (urticaria); or difficulty breathing. These may be signs of a severe allergic reaction (angioedema) that requires emergency treatment.
Common
May affect up to 1 in 10 patients
- Drowsiness and daytime sleepiness
- Dizziness
- Headache
- Worsened insomnia (rebound effect)
- Memory problems (anterograde amnesia)
- Hallucinations
- Agitation and nightmares
- Fatigue
- Back pain
- Gastrointestinal disturbances (diarrhea, nausea, vomiting, abdominal pain)
- Depression
- Attention and speech difficulties
Uncommon
May affect up to 1 in 100 patients
- Confusion
- Irritability
- Double vision (diplopia)
- Restlessness
- Aggression
- Complex sleep behaviors (sleepwalking, sleep-driving, sleep-eating, making phone calls while asleep)
- Skin rash and itching
- Abnormal sweating
- Elevated liver enzymes
- Muscle weakness
Rare
May affect up to 1 in 1,000 patients
- Decreased level of consciousness
- Changes in libido (sex drive)
- Unsteady gait (ataxia)
- Falls (especially in elderly patients)
- Urticaria (hives)
- Liver damage
Very Rare
May affect up to 1 in 10,000 patients
- Delusions
- Drug dependence (physical and psychological)
Frequency Not Known
Cannot be estimated from available data
- Anger and behavioral changes
- Tolerance (decreased effectiveness over time)
- Delirium (acute confusion and disorientation)
If you experience any side effects, including those not listed above, report them to your healthcare provider. You can also report suspected adverse reactions directly to your national pharmacovigilance authority (e.g., the FDA MedWatch program in the US, the Yellow Card scheme in the UK, or the EMA EudraVigilance system in the EU). Reporting helps to continuously monitor the safety profile of medicines.
How Should You Store Zolpidem?
Quick Answer: Store zolpidem at room temperature in the original packaging, away from light and moisture. Keep all medications out of the reach of children.
Proper storage of medications is essential to maintain their safety and effectiveness. Follow these guidelines for storing zolpidem:
- Keep out of sight and reach of children. Store the medication in a secure location, as accidental ingestion by children can cause serious harm.
- Store in original packaging. Keep the blister pack inside the outer carton to protect the tablets from light and moisture.
- Room temperature storage. No special temperature conditions are required. Store at normal room temperature (below 25°C / 77°F).
- Check the expiration date. Do not use zolpidem after the expiry date printed on the packaging (marked as EXP). The expiry date refers to the last day of the stated month.
- Safe disposal. Do not dispose of medications via the household waste or down the drain. Return unused or expired zolpidem to your pharmacy or use a designated medication take-back program to protect the environment.
As zolpidem is a controlled substance in many countries, additional care should be taken to store it securely and prevent misuse or diversion. Do not share your medication with anyone else, even if they have similar symptoms.
What Does Zolpidem Contain?
Quick Answer: Zolpidem film-coated tablets contain zolpidem tartrate as the active substance (5 mg or 10 mg), along with inactive ingredients including lactose monohydrate, microcrystalline cellulose, and a film-coating.
Understanding the full composition of your medication is important, particularly if you have known allergies or intolerances to specific excipients.
Active substance: Zolpidem tartrate 5 mg or 10 mg per film-coated tablet.
Inactive ingredients (excipients):
- Lactose monohydrate
- Microcrystalline cellulose
- Pregelatinized starch
- Sodium starch glycolate
- Colloidal anhydrous silica
- Magnesium stearate
Film coating:
- Hypromellose
- Titanium dioxide (E 171)
- Talc
- Macrogol (polyethylene glycol)
Zolpidem tablets contain lactose monohydrate. If you have been told by your doctor that you have an intolerance to certain sugars, consult your doctor before taking this medicine.
Tablet appearance:
- 5 mg tablet: White or almost white, round, biconvex film-coated tablet.
- 10 mg tablet: White or almost white, oval film-coated tablet with a score line on one side. The tablet can be divided into two equal 5 mg doses.
Zolpidem is available in blister packs containing 7, 10, 14, 20, 21, 28, 30, 35, 98, 100, or 105 tablets. Not all pack sizes may be marketed in every country.
Frequently Asked Questions About Zolpidem
Yes, zolpidem can cause both physical and psychological dependence, especially when used for longer than 4 weeks or at higher doses than recommended. The risk is greater in patients with a history of alcohol, drug, or medication abuse, and in those with mental health disorders. To minimize the risk of dependence, always use the lowest effective dose for the shortest possible duration. When it is time to stop, your doctor will typically recommend a gradual dose reduction rather than abrupt discontinuation to avoid withdrawal symptoms.
Zolpidem is a rapid-acting medication that typically begins working within 15 to 30 minutes after oral administration. Its short half-life of approximately 2.5 hours means it is designed primarily to help with falling asleep rather than staying asleep throughout the entire night. Because of this rapid onset, it should only be taken immediately before getting into bed, and you should be ready to sleep when taking it.
Yes, zolpidem is known to cause complex sleep behaviors, which can include sleepwalking, sleep-driving, making phone calls, preparing and eating food, and engaging in sexual activity while not fully awake. Patients often have no memory of these events the next morning. These behaviors can result in serious injury to the patient or others. If you or someone you live with notices any such behavior, you should stop taking zolpidem immediately and contact your doctor. The risk is increased by alcohol consumption and concurrent use of other CNS depressants.
Zolpidem is intended for short-term use only, typically no longer than 2 to 4 weeks including the tapering period. Daily long-term use significantly increases the risk of tolerance (needing progressively higher doses) and physical dependence. If your insomnia persists beyond 2 weeks of treatment, it is important to consult your doctor, as the underlying cause may require a different treatment approach. Cognitive behavioral therapy for insomnia (CBT-I) is recommended by international guidelines as the first-line treatment for chronic insomnia and has been shown to be more effective than medication in the long term.
Do not take a double dose to make up for a missed dose. If you forget to take zolpidem at bedtime but remember during the night, only take it if you still have at least 7 to 8 hours of sleep remaining before you need to be awake and alert. If less time remains, skip the missed dose entirely and take your next regular dose the following night. Never take two doses to compensate.
Elderly patients are more sensitive to the effects of zolpidem and face a higher risk of adverse effects including falls, next-day drowsiness, confusion, and cognitive impairment. For this reason, the recommended dose for patients over 65 years is 5 mg (half the standard adult dose). Treatment duration should be as short as possible. Healthcare providers should carefully assess the risk-benefit balance in elderly patients and consider non-pharmacological alternatives for insomnia management whenever possible.
References
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- World Health Organization (WHO). WHO Model List of Essential Medicines, 23rd List (2023). Geneva: World Health Organization; 2023.
- British National Formulary (BNF). Zolpidem tartrate — Drug monograph. National Institute for Health and Care Excellence (NICE). bnf.nice.org.uk. Accessed January 2026.
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