Drug Monograph

Zolpidem

Brand names: Ambien (IR tablet), Ambien CR (extended-release tablet), Edluar (sublingual tablet), Intermezzo (low-dose sublingual for middle-of-night awakening), Zolpimist (oral spray)
Imidazopyridine sedative-hypnotic (“Z-drug”); selective GABAA α1-subunit positive allosteric modulator · Oral & sublingual · DEA Schedule IV · FDA boxed warning (complex sleep behaviors)
Pharmacokinetic Profile
Half-Life
~2.5 h (IR); ~2.8 h (CR); prolonged in hepatic impairment and elderly
Metabolism
Hepatic, primarily CYP3A4 (~61%); CYP2C9, CYP1A2, CYP2D6 (minor)
Protein Binding
~92%
Bioavailability
~70% oral
Tmax
~1.6 h (IR); biphasic ~1.5 h then sustained (CR); 35–75 min (SL)
Clinical Information
Drug Class
Imidazopyridine non-benzodiazepine sedative-hypnotic (“Z-drug”)
Available Doses
IR tablet (Ambien): 5, 10 mg
ER tablet (Ambien CR): 6.25, 12.5 mg
SL tablet (Edluar): 5, 10 mg
SL tablet (Intermezzo): 1.75, 3.5 mg
Oral spray (Zolpimist): 5 mg/spray
Route
Oral, sublingual, oromucosal spray
Renal Adjustment
No formal adjustment; monitor in severe impairment
Hepatic Adjustment
Required — 5 mg IR or 6.25 mg CR; avoid in severe impairment
Pregnancy
Use only if benefits outweigh risk; neonatal sedation/respiratory depression reported
Lactation
Excreted in breast milk; caution advised
Schedule / Legal Status
DEA Schedule IV controlled substance
Boxed Warning
Yes — complex sleep behaviors (added 2019)
Generic Available
Yes (IR, CR, sublingual)
Rx

Indications

IndicationApproved PopulationTherapy TypeStatus
Short-term treatment of insomnia — sleep initiation (Ambien, Edluar, Zolpimist)AdultsMonotherapy; efficacy demonstrated up to 35 days in registration trialsFDA Approved
Insomnia — sleep onset and/or maintenance (Ambien CR)AdultsMonotherapyFDA Approved
Middle-of-the-night awakening with difficulty returning to sleep (Intermezzo low-dose SL)Adults with ≥4 h of bedtime remaining before planned awakeningMonotherapy; PRN dosing only, max 1 dose per nightFDA Approved
Disorders of consciousness (paradoxical arousal in vegetative or minimally conscious states)Selected patients with brain injuryInvestigationalOff-Label
Restless legs syndrome — refractory casesAdultsAdjunctive when first-line agents failOff-Label

Zolpidem was approved by the FDA in 1992 for the short-term management of insomnia. Despite its widespread use, current clinical practice guidelines (American Academy of Sleep Medicine 2017 and American College of Physicians 2016) position cognitive behavioural therapy for insomnia (CBT-I) as the first-line treatment for chronic insomnia disorder, with pharmacotherapy reserved for patients in whom CBT-I is unavailable, declined, or insufficient. When pharmacotherapy is selected, zolpidem remains one of several options with a conditional, weak recommendation for sleep-onset insomnia. Treatment duration in registration trials extended only to 35 days, and the longest controlled trial (zolpidem CR, 24 weeks) supports up to 6 months of intermittent dosing; longer use carries increasing concern for tolerance, dependence, and complex sleep behaviours.

Common Off-Label Uses

Disorders of consciousness — small case series and uncontrolled trials describe transient awakening or improved responsiveness in selected patients with chronic vegetative or minimally conscious states. The effect is unpredictable and not sustained. Evidence quality: very low.

Refractory restless legs syndrome (RLS) — sometimes used at bedtime for patients who fail dopamine agonists, alpha-2-delta ligands, or iron repletion. Evidence quality: low.

Anxiety, jet lag, transient situational sleep difficulty — commonly prescribed but not supported by guideline-level evidence. Evidence quality: low.

Zolpidem is not indicated for, and should not be used to treat: anxiety disorders, primary depression, alcohol or sedative withdrawal, paediatric insomnia, or chronic non-restorative sleep without an evaluation for comorbid sleep-disordered breathing.

Dose

Dosing

Zolpidem dosing has been formally sex-stratified since the FDA’s 2013 label revision: women clear zolpidem more slowly than men and have approximately 45% higher peak plasma concentrations at the same dose, with corresponding higher rates of next-morning impairment. Women should be started on the lower dose; men may be started on either the lower or standard dose. Doses are presented per formulation because zolpidem products are not interchangeable.

Clinical ScenarioStarting DoseMaintenance DoseMaximum DoseNotes
Sleep-onset insomnia — adult women (Ambien IR)5 mg PO at bedtime5–10 mg at bedtime10 mg/nightIncrease to 10 mg only if 5 mg is ineffective; 10 mg increases next-day impairment risk
Take with ≥7–8 h sleep available; avoid food in preceding minutes
Sleep-onset insomnia — adult men (Ambien IR)5 or 10 mg PO at bedtime5–10 mg at bedtime10 mg/nightFDA prefers the 5 mg starting dose to minimize next-morning impairment
Single dose only; do not re-dose during the same night
Sleep-onset and maintenance insomnia — adult women (Ambien CR)6.25 mg PO at bedtime6.25 mg at bedtime12.5 mg/nightHigher next-morning impairment than IR at equal dose; do not split or crush
CR formulation has biphasic release for maintained sleep
Sleep-onset and maintenance insomnia — adult men (Ambien CR)6.25 or 12.5 mg PO at bedtime6.25–12.5 mg at bedtime12.5 mg/nightFDA prefers the 6.25 mg starting dose
Take whole; do not split, crush, or chew
Sleep-onset insomnia — sublingual (Edluar)5 mg SL women; 5 or 10 mg SL men5–10 mg SL at bedtime10 mg/nightPlace under tongue and allow to disintegrate; do not swallow whole or with water
Slightly faster onset than oral tablet
Middle-of-the-night awakening (Intermezzo SL)1.75 mg SL women; 3.5 mg SL menSame as starting dose1 dose per nightUse only if ≥4 h of intended sleep remain before planned awakening; do not use with alcohol or any other sleep aid
Distinct low-dose sublingual product; not interchangeable with bedtime zolpidem
Sleep-onset insomnia — oral spray (Zolpimist)5 mg (1 spray) women; 5 or 10 mg men5–10 mg at bedtime10 mg/nightSpray over the tongue immediately before bed; prime device on first use
Useful for patients with swallowing difficulty

Dose Adjustments in Special Populations

PopulationRecommendationRationale
Elderly or debilitated patients5 mg IR (or 6.25 mg CR) regardless of sex; 1.75 mg IntermezzoGreater sensitivity to sedation; falls risk; reduced clearance
Hepatic impairment5 mg IR (or 6.25 mg CR; 1.75 mg Intermezzo); avoid in severe impairmentReduced first-pass metabolism prolongs half-life and elevates exposure
Renal impairmentNo formal dose adjustment<1% of zolpidem is excreted unchanged in urine
Concomitant CNS depressant (e.g., opioid, benzodiazepine)Consider lower zolpidem dose or avoid combinationAdditive CNS and respiratory depression
Pediatric (<18 years)Not recommendedDid not improve sleep latency in trials; high rate of psychiatric/CNS adverse effects (hallucinations 7%, dizziness 23.5%, headache 12.5%)

Discontinuation

Zolpidem should be discontinued promptly if a patient experiences any episode of complex sleep behaviour (boxed warning), if therapeutic benefit is lost, or after the shortest clinically appropriate course. Although the Ambien label states that recommended-dose use does not produce objective polysomnographic rebound insomnia, withdrawal signs and symptoms (anxiety, tremor, sweating, sleep disturbance) have been reported with abrupt cessation after prolonged or higher-dose use. For patients on chronic therapy, taper gradually rather than stop abruptly; concurrent CBT-I support during weaning improves outcomes.

Clinical Pearl — Why the Sex-Specific Starting Dose Matters

The FDA halved the recommended bedtime dose for women in 2013 after pharmacokinetic studies showed approximately 45% higher zolpidem Cmax and AUC in females than males at the same dose, driven primarily by lower CYP3A4 activity and clearance. The implication is practical: a woman taking 10 mg at 11 PM may have residual blood levels capable of impairing driving at 7 AM. Always start women on 5 mg IR or 6.25 mg CR, document the rationale, and counsel explicitly on next-morning driving risk.

PK

Pharmacology

Mechanism of Action

Zolpidem is an imidazopyridine that binds with high affinity and relative selectivity to GABAA receptors containing the α1 subunit (formerly designated the ω1 or BZ1 benzodiazepine receptor subtype). It binds at an allosteric site distinct from the GABA-binding site and potentiates the chloride conductance produced by GABA, hyperpolarizing neuronal membranes and producing sedation. Compared with classical benzodiazepines, the α1 selectivity of zolpidem yields predominantly sedative effects with minimal anxiolytic, muscle-relaxant, or anticonvulsant activity at hypnotic doses, although these distinctions narrow at supratherapeutic doses. The drug’s effects are reversed by flumazenil. Selectivity is incomplete: at higher doses (>10 mg), zolpidem shows additional binding to α2– and α3-containing receptors, which is hypothesized to contribute to abuse liability, withdrawal phenomena, and complex sleep behaviours.

ADME Profile

ParameterValueClinical Implication
AbsorptionOral bioavailability ~70% (first-pass metabolism); Tmax ~1.6 h (IR), biphasic with primary peak at ~1.5 h then sustained release (CR), 35–75 min (sublingual). Food delays absorption and reduces CmaxTake on an empty stomach, immediately before bedtime; sublingual onset is faster than tablet
DistributionVd ~0.54 L/kg (small); plasma protein binding ~92% (largely to albumin); crosses placenta and is excreted in breast milkHypoalbuminaemia may modestly increase free fraction; counsel breastfeeding mothers
MetabolismExtensively hepatic; CYP3A4 is the principal enzyme (~61%), with smaller contributions from CYP2C9 (~22%), CYP1A2 (~14%), and CYP2D6 (~2.5%). All major metabolites are pharmacologically inactiveSignificant interactions with CYP3A4 inhibitors (azoles, macrolides, ritonavir) and inducers (rifampin, St John’s wort, carbamazepine)
EliminationEliminated as inactive metabolites in urine (and faeces); <1% excreted unchanged in urine. Mean elimination t½ ~2.5 h (IR) and ~2.8 h (CR); prolonged in elderly and hepatic impairmentShort half-life favours sleep-onset use; no significant accumulation; renal impairment requires no dose change
SE

Side Effects

The frequency data below come from the Ambien FDA prescribing information, derived from short-term (up to 10 nights, n=685) and longer-term (28–35 nights, n=152) placebo-controlled trials at doses up to 10 mg. Adverse-effect rates rise with the 10 mg dose compared with 5 mg, with concomitant CNS depressants, and in women.

≥10% Very Common
Adverse EffectIncidenceClinical Note
None reported in adult Ambien controlled trials at the ≥10% thresholdThe Ambien FDA PI tables list no adult adverse event with incidence ≥10% at recommended doses (≤10 mg). The most frequent adverse events fall in the 1–10% Common tier. In paediatric ADHD-insomnia trials (not an approved use), dizziness reached 23.5% and headache 12.5% — see Cautions section
1–10% Common
Adverse EffectIncidence (zolpidem vs placebo)Clinical Note
Drowsiness (longer-term use)8% vs 5%Most common dose-related effect; warn about morning carry-over
Headache (short-term)7% vs 6%Rate close to placebo; usually transient
Dizziness (longer-term use)5% vs 1%Increased fall risk, especially elderly
“Allergy” symptoms (longer-term use)4% vs 1%WHO-coded term covering rhinitis-type and minor hypersensitivity reports; not anaphylaxis
Sinusitis (longer-term use)4% vs 2%Reported during 28–35-night studies
Drugged feeling (longer-term use)3% vs 0%Distinct adverse-event term; suggests CNS impairment
Pharyngitis (longer-term use)3% vs 1%Generally mild
Dry mouth (longer-term use)3% vs 1%Manage symptomatically
Diarrhoea (longer-term use)3% vs 2%Generally mild
Lethargy (longer-term use)3% vs 1%Distinct from somnolence in clinical trials terminology
Back pain (longer-term use)3% vs 2%Reported with chronic use
Lightheadedness (longer-term use)2% vs 1%Often orthostatic-type
Drowsiness (short-term use)2% vs 0%Statistically significant vs placebo at this short-term timepoint
Constipation (longer-term use)2% vs 1%Manage with hydration and fibre
Depression (longer-term use)2% vs 1%Caution in patients with pre-existing depression
Palpitations (longer-term use)2% vs 0%Usually benign; evaluate if symptomatic
Influenza-like symptoms (longer-term use)2% vs 0%Reported during chronic-use trials
Abdominal pain, rash, abnormal dreams, amnesia, sleep disorder, chest pain (longer-term use)~1–2% eachAnterograde amnesia is dose-related and most prominent at 10–20 mg doses
Serious Regardless of Frequency
Adverse EffectEstimated FrequencyTypical OnsetRequired Action
Complex sleep behaviours (sleep-driving, sleep-eating, sleep-walking, sleep-phone calls, with amnesia for the event) — boxed warningRare; 66 cases identified by FDA across 26 years (61 with zolpidem) before 2019 boxed warningCan occur after a single dose, even at lowest recommended dosePermanent discontinuation; FDA contraindication to rechallenge any Z-drug after one episode
Anaphylaxis / angioedema (tongue, glottis, larynx)RareAfter first or any subsequent doseDiscontinue; do not rechallenge; emergency airway management if needed
Worsening depression / suicidal ideation / completed suicidePostmarketing reports; intentional overdose more common in depressed patientsVariablePrescribe smallest tablet quantity feasible; screen for depression; refer for psychiatric evaluation if symptoms emerge
Respiratory depressionRare at therapeutic doses; greater risk with respiratory impairment, sleep apnea, myasthenia gravis, opioid co-prescriptionWithin hours of dosingAvoid in compromised respiratory function; emergency support for severe cases; flumazenil reverses GABAA effect
Hallucinations and other behavioural changes (decreased inhibition, agitation, depersonalization, bizarre behaviour)<1% in adults; 7% in paediatric ADHD trial (vs 0% placebo)Hours after doseDiscontinue; immediate clinical evaluation
Falls and fractures (particularly hip fracture in elderly)Increased risk in elderly; ~1.5% in non-US trials, predominantly >70 years and >10 mg dosesDuring night-time awakenings or next morningReduce dose; counsel on night-time mobility; consider deprescribing in frail elderly
Tolerance, abuse, and dependenceSchedule IV; risk increased with prior substance-use history, higher doses, longer durationWeeks to monthsLimit duration; avoid in active substance-use disorder; taper rather than stop abruptly
Withdrawal symptoms (anxiety, tremor, sweating, sleep disturbance, rarely seizures)Postmarketing reports after rapid taper or abrupt stop1–3 days after cessationTaper gradually; consider cross-taper to longer-acting agent in heavy or long-term users
CNS depression in overdose (somnolence to coma; hypotension; rarely fatal alone but often combined with alcohol/opioids in fatalities)Dose-dependentWithin 1–2 h of ingestionSupportive care; flumazenil reverses CNS effects; activated charcoal if recent ingestion; airway support if severe
Discontinuation Treatment Cessation Rates
Pooled US trials (n=1,701, all doses)
~4%
Top reasons: nausea (0.6%), drowsiness (0.5%), headache (0.5%), vomiting (0.5%), dizziness (0.4%).
Pooled non-US trials (n=1,959)
~4%
Top reasons: daytime drowsiness (1.1%), dizziness/vertigo (0.8%), amnesia (0.5%), nausea (0.5%), falls (0.4%).
Reason for DiscontinuationApprox. IncidenceContext
Daytime drowsiness~0.5–1.1%Most common cause across both US and non-US trial pools
Nausea / vomiting~0.5–1.1%GI intolerance; consider dose reduction before discontinuation
Falls (non-US trials, elderly)~0.4%93% of falls were in patients ≥70 years, 82% on doses >10 mg
Complex sleep behaviourMandatory permanent discontinuation regardless of frequencyPer FDA boxed warning & contraindication added 2019
Managing Next-Morning Impairment — The Highest-Yield Counselling Point

Next-morning psychomotor impairment is dose-related, more pronounced with the CR formulation, more pronounced in women, and worst when zolpidem is taken with less than a full 7–8 hour sleep window or in combination with alcohol or other CNS depressants. Driving simulator studies have demonstrated impairment 8 hours after a 10 mg dose in women. Practical strategies: (1) start women on 5 mg IR or 6.25 mg CR; (2) verify 7–8 h available before any planned driving; (3) explicitly forbid alcohol on dosing nights; (4) educate that subjective alertness does not equal objective fitness to drive; (5) reassess every 1–3 months and limit chronic prescriptions.

Int

Drug Interactions

Zolpidem’s interactions are dominated by two mechanisms: pharmacodynamic synergy with other CNS depressants (the leading driver of overdose deaths and complex sleep behaviours) and pharmacokinetic modulation through CYP3A4 (the principal metabolic enzyme).

Major Sodium oxybate / oxybate salts (Xyrem, Xywav)
MechanismPharmacodynamic synergy on CNS depression
EffectProfound sedation and respiratory depression
ManagementContraindicated combination per oxybate label
FDA PI
Major Opioids (oxycodone, hydrocodone, morphine, etc.)
MechanismAdditive CNS and respiratory depression
EffectIncreased risk of overdose, respiratory depression, complex sleep behaviour, death
ManagementAvoid combination; if essential, use lowest effective doses, shortest duration, counsel on naloxone availability
FDA PI
Major Alcohol
MechanismAdditive CNS depression; demonstrated additive psychomotor impairment in healthy volunteers
EffectMarked sedation, complex sleep behaviour, falls, fatal respiratory depression
ManagementAvoid alcohol entirely on dosing nights; specifically prohibited with Intermezzo
FDA PI
Major Benzodiazepines and other Z-drugs
MechanismSame site of action; additive GABAergic depression
EffectExcessive sedation, amnesia, cognitive impairment
ManagementAvoid co-administration; co-use of two sedative-hypnotics is not recommended
FDA PI
Major Strong CYP3A4 inhibitors (ketoconazole, itraconazole, ritonavir, clarithromycin)
MechanismDecreased zolpidem clearance via the dominant CYP3A4 pathway
EffectIncreased zolpidem exposure; ketoconazole increases zolpidem pharmacodynamic effects
ManagementUse lower starting dose of zolpidem; consider a non-Z-drug alternative
FDA PI
Moderate Strong CYP3A4 inducers (rifampin, carbamazepine, phenytoin, St John’s wort)
MechanismAccelerated zolpidem clearance via CYP3A4 induction
EffectReduced exposure and loss of hypnotic efficacy
ManagementAnticipate reduced effect; avoid dose escalation as primary strategy; consider an alternative agent
FDA PI
Moderate Sertraline
MechanismIncreases zolpidem exposure (mechanism not fully established)
EffectGreater sedation; in trials of SSRI-treated patients, 4 of 7 zolpidem discontinuations were related to impaired concentration, depression, or manic reaction
ManagementUse lowest zolpidem dose; monitor for next-day impairment
FDA PI
Moderate Fluoxetine
MechanismReduction of zolpidem clearance; ~17% increase in zolpidem half-life with multiple dosing
EffectModest increase in zolpidem exposure; no additive psychomotor effect demonstrated
ManagementStandard dosing usually acceptable; monitor for excess sedation
FDA PI
Moderate Imipramine and chlorpromazine
MechanismPharmacodynamic; additive CNS depression
EffectDecreased alertness; chlorpromazine combination also impaired psychomotor performance in volunteer studies
ManagementCounsel about additive sedation; minimize concurrent use
FDA PI
Minor Food
MechanismDelayed gastric emptying slows absorption
EffectDelayed onset and reduced Cmax; may impair sleep-onset effect
ManagementTake immediately before bed on an empty stomach
FDA PI
Mon

Monitoring

Zolpidem requires no laboratory monitoring, but it requires structured clinical follow-up. The highest-yield surveillance addresses the boxed warning (complex sleep behaviours), next-day functional impairment, dependence, and emerging contributors to insomnia that may have been missed.

  • Sleep diary & insomnia metrics Baseline; reassess at 2–4 weeks
    Routine
    Track sleep latency, total sleep time, wake after sleep onset, and morning function. Validated tools: Insomnia Severity Index (ISI), Pittsburgh Sleep Quality Index (PSQI).
  • Complex sleep behaviour screen Each visit, with bed partner if available
    Routine
    Ask explicitly about sleep-walking, sleep-driving, sleep-eating, sleep-phone use, and unexplained morning evidence of activity. A single episode mandates permanent discontinuation per FDA contraindication.
  • Next-day function Each visit during titration; periodically thereafter
    Routine
    Ask about morning sedation, attention, and driving safety. Subjective alertness is unreliable; counsel that 7–8 h sleep window is mandatory.
  • Mood & suicidality Each visit
    Routine
    Insomnia is frequently a symptom of depression. Screen with PHQ-9; intentional overdose is more common in depressed patients.
  • Need for ongoing therapy Re-evaluate at 7–10 days; then 1–3 monthly
    Routine
    Per FDA labelling, persistent insomnia after 7–10 days warrants evaluation for psychiatric or medical causes. Reassess goals, taper consideration, CBT-I referral.
  • Substance use / aberrant behaviours Each visit; PDMP check at refill
    Routine
    Schedule IV drug. Check state Prescription Drug Monitoring Program. Watch for early refill requests, lost prescriptions, dose escalation requests.
  • Falls (elderly) Each visit if ≥65 years
    Trigger-based
    Z-drugs are designated potentially inappropriate by the AGS Beers Criteria. Document risk-benefit; consider deprescribing.
  • Sleep-disordered breathing screen Before initiation; if symptoms emerge
    Trigger-based
    Snoring, witnessed apnea, daytime sleepiness, or BMI >30 warrant evaluation for OSA before chronic zolpidem; sedative-hypnotics can worsen apnea.
  • Hepatic function If clinical concern; not routinely required
    Trigger-based
    Hepatic impairment markedly elevates zolpidem exposure; reduce dose or avoid in severe disease.
CI

Contraindications & Cautions

Absolute Contraindications

  • Prior episode of complex sleep behaviour (sleep-driving, sleep-walking, sleep-eating, or other behaviours while not fully awake) attributed to zolpidem, eszopiclone, or zaleplon — FDA contraindication added April 2019 alongside the boxed warning.
  • Known hypersensitivity to zolpidem, including prior anaphylaxis or angioedema involving the tongue, glottis, or larynx.

Relative Contraindications — Specialist Input Recommended

  • Active alcohol or substance-use disorder — high risk of misuse, overdose, and complex sleep behaviours.
  • Severe hepatic impairment — clearance is markedly reduced; if essential, use lowest dose with close observation.
  • Significant respiratory disease — severe COPD, untreated obstructive sleep apnea, neuromuscular disease (myasthenia gravis), or hypoventilation syndromes; risk of respiratory depression.
  • Suicidal ideation or active major depressive disorder — intentional overdose risk; prescribe smallest quantity feasible and screen carefully.
  • Concurrent opioid therapy — if combination is unavoidable, use lowest doses, provide naloxone, monitor closely.
  • Pregnancy — use only if benefit outweighs risk; neonatal sedation, respiratory depression, and withdrawal have been reported, particularly with use near delivery.
  • Older adults ≥65 years — AGS Beers Criteria designate zolpidem as potentially inappropriate; falls and cognitive impairment are amplified.

Use with Caution

  • Operating motor vehicles or heavy machinery the morning after a dose, particularly with the 10 mg IR or 12.5 mg CR dose, in women, or with less than 7–8 hours of sleep.
  • Lactation — zolpidem is excreted in breast milk; observe nursing infants for sedation.
  • Patients with a personal or family history of parasomnias or sleep-walking — baseline risk for complex sleep behaviour may be increased.
  • Children and adolescents under 18 years — not recommended; in the only paediatric trial, sleep latency was not improved versus placebo and adverse-event rates were substantially higher (hallucinations 7%, dizziness 23.5%, headache 12.5%).
FDA Boxed Warning Complex Sleep Behaviours (added April 30, 2019)

Complex sleep behaviours including sleep-walking, sleep-driving, and engaging in other activities while not fully awake have occurred with zolpidem and other Z-drugs (eszopiclone, zaleplon). These behaviours have resulted in serious injuries and deaths, including burns, drowning, fatal motor-vehicle collisions, gunshot wounds, hypothermia, and suicide attempts. They can occur in patients with no prior history of such events, after the first dose, and at the lowest recommended dose. Risk is increased by alcohol and other CNS depressants but events have occurred without these.

Discontinue zolpidem immediately and permanently if a patient experiences any complex sleep behaviour. Zolpidem is contraindicated in patients with a history of complex sleep behaviour after taking any Z-drug; do not rechallenge with zolpidem, eszopiclone, or zaleplon. Counsel every patient before starting therapy and at each refill.

Pt

Patient Counselling

Purpose of Therapy

Zolpidem is a short-acting sleep medication used to help with falling asleep (and, with the extended-release form, staying asleep). It works on the same brain receptor system as benzodiazepines but with a more focused action that produces sedation. Zolpidem is intended for short-term use; cognitive behavioural therapy for insomnia (CBT-I) addresses the root causes of insomnia and is the recommended first-line treatment, with medications added when behavioural therapy is unavailable, declined, or insufficient.

How to Take

Take zolpidem only when you are ready to go to bed and have at least 7–8 hours available before you need to wake up (4 hours for Intermezzo). Take it on an empty stomach — food slows absorption and may keep the medication from working in time. Do not take a second dose during the same night. Do not crush, chew, or split extended-release (CR) tablets. For the sublingual tablet, place under the tongue and allow it to dissolve without swallowing or drinking water. Never combine zolpidem with alcohol, opioid pain medication, or other sleep aids.

Sleep-Driving and Other Activities While Asleep — Critical
Tell patient Some people taking zolpidem have driven, walked, eaten, or made phone calls while not fully awake and have no memory of these events afterwards. This can occur after the first dose, even at the lowest dose, and has caused injuries and deaths. Watch for signs the next morning: car keys moved, food eaten, calls made, or items disturbed. Ask a bed partner or family member to tell you if they notice unusual nighttime activity.
Call prescriber Stop zolpidem immediately and call your prescriber if any complex sleep behaviour occurs. After even one episode, you should not take zolpidem or other sleep medications in the same class (eszopiclone, zaleplon) again.
Next-Morning Drowsiness & Driving
Tell patient Even if you feel fully awake, your reactions and judgment may be impaired the morning after a dose, especially with the 10 mg dose, the extended-release form, in women, or after less than 7–8 hours of sleep. Plan a full night’s sleep window before you take a dose. Avoid driving until you know how the medication affects you the next day.
Call prescriber If morning grogginess interferes with school, work, or driving, or if you have a near-miss while driving the day after a dose.
Alcohol & Other Sedatives
Tell patient Do not drink alcohol on nights you take zolpidem — even small amounts can sharply worsen sedation and increase the risk of complex sleep behaviour, falls, and respiratory depression. Tell your prescriber about every other medication, including over-the-counter sleep aids, antihistamines like diphenhydramine, opioid pain medications, and anti-anxiety medications.
Call prescriber Before starting any new sedating medication, including over-the-counter sleep products and herbal remedies.
Memory and Behaviour
Tell patient Some people experience memory gaps for events after taking zolpidem (anterograde amnesia), or behave out of character (more outgoing, agitated, or aggressive). Hallucinations are uncommon but possible. These effects are more likely with higher doses or alcohol use.
Call prescriber For any new memory problems, hallucinations, or unusual behavioural changes.
Mood & Depression
Tell patient If you have a history of depression, your symptoms could worsen on zolpidem. Trouble sleeping is itself a common symptom of depression and may be telling you something deeper needs attention.
Call prescriber For worsening low mood, hopelessness, or any thoughts of self-harm. These warrant urgent contact and may signal that zolpidem is not the right treatment.
Tolerance & Stopping
Tell patient Zolpidem is intended for short-term use. With long-term use, you may need higher doses to achieve the same effect (tolerance) and may experience rebound insomnia, anxiety, or other symptoms when stopping. Do not increase the dose on your own. Plan a gradual taper with your prescriber rather than stopping suddenly.
Call prescriber Before stopping if you have taken zolpidem for several weeks or longer; for severe rebound insomnia, agitation, sweating, tremor, or seizures during a planned taper.
Falls & Night-Time Mobility
Tell patient If you need to get up at night to use the bathroom, take it slowly and turn on a light. Falls and fractures are more common on zolpidem, especially in older adults. Make sure your bedroom is free of trip hazards (loose rugs, cords).
Call prescriber After any fall while taking zolpidem; for new dizziness or balance problems.
Pregnancy & Breastfeeding
Tell patient Zolpidem can pass to a baby during pregnancy or through breast milk. Babies born to mothers using zolpidem near delivery have had sedation, low muscle tone, and breathing problems. Discuss with your prescriber if you are planning pregnancy, become pregnant, or are breastfeeding.
Call prescriber As soon as pregnancy is suspected or confirmed.
Ref

Sources

Regulatory (PI / SmPC)
  1. Ambien (zolpidem tartrate) tablets — full prescribing information. U.S. Food and Drug Administration; 2013 revision incorporating sex-specific dosing. Available at accessdata.fda.gov Primary source for adult dosing, adverse-event tables, drug interactions, pharmacokinetics, and pediatric trial data (hallucinations 7% in ADHD study).
  2. Intermezzo (zolpidem tartrate) sublingual tablets — full prescribing information. U.S. Food and Drug Administration. Available at accessdata.fda.gov Primary source for low-dose middle-of-the-night dosing (1.75 mg women, 3.5 mg men), 4-hour sleep window, and contraindication on prior complex sleep behaviour.
  3. FDA Drug Safety Communication: FDA adds Boxed Warning for risk of serious injuries caused by sleepwalking with certain prescription insomnia medicines. April 30, 2019. Available at fda.gov Source for the boxed warning and contraindication on complex sleep behaviours, based on 66 cases (61 with zolpidem) reviewed over 26 years.
  4. FDA Safety Communication: Risk of next-morning impairment after use of insomnia drugs; FDA requires lower recommended doses for certain drugs containing zolpidem. January 2013. Available at fda.gov Source for the sex-specific dosing reduction (women: 5 mg IR / 6.25 mg CR) and the underlying pharmacokinetic rationale.
Key Clinical Trials
  1. Krystal AD, Erman M, Zammit GK, Soubrane C, Roth T; ZOLONG Study Group. Long-term efficacy and safety of zolpidem extended-release 12.5 mg, administered 3 to 7 nights per week for 24 weeks, in patients with chronic primary insomnia: a 6-month, randomized, double-blind, placebo-controlled, parallel-group, multicenter study. Sleep. 2008;31(1):79–90. doi:10.1093/sleep/31.1.79 Largest long-term efficacy trial of zolpidem CR demonstrating maintained effect over 6 months in chronic primary insomnia.
  2. Roth T, Soubrane C, Titeux L, Walsh JK; Zoladult Study Group. Efficacy and safety of zolpidem-MR: a double-blind, placebo-controlled study in adults with primary insomnia. Sleep Med. 2006;7(5):397–406. doi:10.1016/j.sleep.2006.04.008 Pivotal trial supporting Ambien CR approval for sleep-onset and maintenance insomnia.
  3. Roth T, Krystal A, Steinberg FJ, Roehrs T, Rosenberg R. Novel sublingual low-dose zolpidem tablet reduces latency to sleep onset following spontaneous middle-of-the-night awakening in insomnia in a randomized, double-blind, placebo-controlled, outpatient study. Sleep. 2013;36(2):189–196. doi:10.5665/sleep.2370 Pivotal trial supporting Intermezzo approval for middle-of-the-night insomnia.
Guidelines
  1. Sateia MJ, Buysse DJ, Krystal AD, Neubauer DN, Heald JL. Clinical practice guideline for the pharmacologic treatment of chronic insomnia in adults: an American Academy of Sleep Medicine clinical practice guideline. J Clin Sleep Med. 2017;13(2):307–349. doi:10.5664/jcsm.6470 AASM 2017 guideline; gives zolpidem a weak recommendation for sleep-onset and sleep-maintenance insomnia, with low-quality evidence.
  2. Qaseem A, Kansagara D, Forciea MA, Cooke M, Denberg TD; Clinical Guidelines Committee of the American College of Physicians. Management of chronic insomnia disorder in adults: a clinical practice guideline from the American College of Physicians. Ann Intern Med. 2016;165(2):125–133. doi:10.7326/M15-2175 ACP 2016 guideline; positions cognitive behavioural therapy for insomnia (CBT-I) as first-line treatment for chronic insomnia disorder in adults.
  3. By the 2023 American Geriatrics Society Beers Criteria® Update Expert Panel. American Geriatrics Society 2023 updated AGS Beers Criteria® for potentially inappropriate medication use in older adults. J Am Geriatr Soc. 2023;71(7):2052–2081. doi:10.1111/jgs.18372 Designates zolpidem and other Z-drugs as potentially inappropriate in older adults due to delirium, falls, and fracture risk.
Mechanistic / Basic Science
  1. Salvá P, Costa J. Clinical pharmacokinetics and pharmacodynamics of zolpidem. Therapeutic implications. Clin Pharmacokinet. 1995;29(3):142–153. doi:10.2165/00003088-199529030-00002 Foundational pharmacokinetic review documenting ~70% bioavailability, ~92% protein binding, Vd ~0.54 L/kg, and short half-life.
  2. Bouchette D, Akhondi H, Patel P. Zolpidem. In: StatPearls. Treasure Island (FL): StatPearls Publishing; updated February 29, 2024. Available at ncbi.nlm.nih.gov/books/NBK442008 Comprehensive overview of zolpidem mechanism, pharmacokinetics, indications, and toxicology.
  3. Mittal N, Mittal R, Gupta MC. Zolpidem for insomnia: a double-edged sword. A systematic literature review on zolpidem-induced complex sleep behaviors. Indian J Psychol Med. 2021;43(5):373–381. doi:10.1177/0253717621992372 Systematic review of complex sleep behaviour cases providing context for the 2019 boxed warning.
Pharmacokinetics / Special Populations
  1. Greenblatt DJ, Harmatz JS, Singh NN, Steinberg F, Roth T, Harris SC, Kapil RP. Pharmacokinetics of zolpidem from sublingual zolpidem tartrate tablets in healthy elderly versus non-elderly subjects. Drugs Aging. 2014;31(10):731–736. doi:10.1007/s40266-014-0211-3 Documents prolonged exposure in elderly subjects supporting age-based dose reduction for the sublingual formulation.
  2. Greenblatt DJ, Harmatz JS, Roth T, Singh NN, Moline ML, Harris SC, Kapil RP. Comparison of pharmacokinetic profiles of zolpidem buffered sublingual tablet and zolpidem oral immediate-release tablet: results from a single-center, single-dose, randomized, open-label crossover study in healthy adults. Clin Ther. 2013;35(5):604–611. doi:10.1016/j.clinthera.2013.03.007 Compares sublingual versus oral absorption kinetics of zolpidem, supporting Edluar/Intermezzo formulation differences.
  3. Park JY, Kim KA, Park PW, Park CW, Shin JG. Effect of CYP3A4 metabolism on sex differences in the pharmacokinetics and pharmacodynamics of zolpidem. Sci Rep. 2021;11(1):19150. doi:10.1038/s41598-021-98689-z Documents 32.5% higher AUC and 9.9% higher Cmax in women, attributed to CYP3A4 activity differences.