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Benzodiazepine Receptor Agonist

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Benzodiazepine Receptor Agonist, Nonbenzodiazepine Sedative-Hypnotic, Nonbenzodiazepine Hypnotic Agent, Z-Drug, Z-Drug Overdose

  • See Also
  1. Insomnia
  2. Zolpidem
  3. Zaleplon
  4. Eszopiclone
  • Medications
  1. Zolpidem (Ambien) or Zolpidem CR
  2. Zaleplon (Sonata)
  3. Eszopiclone (Lunesta)
  • Adverse Effects
  1. Headache
  2. Dizziness
  3. Nausea
  4. Complex Parasomnias such as Sleepwalking (FDA black box warning)
  • Precautions
  1. Avoid in over age 65 years old (See Beers List)
  2. These agents have a duration of effect that extends past the time patients awaken
  3. Long acting agents (e.g. Eszopiclone or Lunesta)
    1. Full dose can impair driving, coordination and memory for up to 11 hours
  4. Since 2013 FDA has moved to lower the maximum doses in women and older patients
    1. Also cautioned about the hang over effect in all patients
  5. FDA Block Box Warning (2019, unusual and potentially dangerous sleep behaviors while on Z-Drugs)
    1. https://www.fda.gov/drugs/drug-safety-and-availability/fda-adds-boxed-warning-risk-serious-injuries-caused-sleepwalking-certain-prescription-insomnia
    2. Rare but serious injuries and deaths related to falls, automobile accidents, Medication Overdoses
  6. FDA Warnings (complete list for Z-Drugs)
    1. http://www.fda.gov/Drugs/DrugSafety/PostmarketDrugSafetyInformationforPatientsandProviders/ucm101557.htm
  • Pharmacokinetics
  1. All are hepatically metabolized by CYP450 3A4
  2. Rapid onset after ingestion (within 30 minutes)
  3. Short Half-Lives (2-4 hours)
  • Drug Interactions
  1. Alcohol and other CNS Depressants have additive effect
  2. Narcotic concurrent use may cause excess sedation
  • Advantages
  1. Less Anticholinergic affect than other hypnotics
  2. Low addictive potential compared with Benzodiazepines
  3. Minimal effect on Sleep Stages
  4. Lack of withdrawal side effects
  5. No rebound Insomnia
  6. Little or no tolerance, effective to 1 year
  • Disadvantages
  1. Non-pharmacologic therapy for Insomnia (e.g. CBT-I) has better longterm outcomes
  1. Findings
    1. Neuro: Altered Level of Consciousness, Ataxia
    2. Cardiovascular: Blood Pressure lability, Tachydysrhythmias, QT Prolongation
    3. Respiratory: Apnea (esp. when combined with other CNS Depressants)
    4. Gastrointestinal: Nausea, Vomiting, Abdominal Pain
  2. Supportive care
    1. See Unknown Ingestion
    2. Flumazenil may be effective (but risk of Benzodiazepine Withdrawal)
    3. Intravenous Fluids as needed for Hypotension
  3. Monitoring
    1. Monitor symptomatic patients until alert (emergency department or observation stay)
    2. Adults with high dose ingestions are often well tolerated (e.g. Zolpidem up to 600 mg)
    3. Children with ingestions of 1 to 2 tablets are typically well tolerated
  4. References
    1. Tomaszewski (2024) Crit Dec Emerg Med 38(10): 35