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Introduction

  • Benzodiazepines are used for numerous acute states in the emergency department, especially

    • agitation

  • IV access is often not available for patients with agitation and alternative routes must be

    • considered; the drug of choice may change depending on the route of administration

  • This handout will focus on the pharmacokinetics of the two most utilized benzodiazepines in the

    • emergency department, lorazepam and midazolam for acute agitation.

Clinical Detail

    Lorazepam

    Midazolam

    Administration

    IV

    IM

    IV

    IM

    IN

    Dose

    Sedation:

  • 5-2 mg

    • Sedation:

  • 5-2mg

    • Sedation:

  • 5-2mg

    • Sedation:

  • 5-5mg

    • Sedation:

  • 1mg/kg

    • Onset

    2-10 min

    (longer for

    anticonvulsant)

    20-30 min

    3-5 min

    5-15 min

    10 min

    Duration

    3 – 6 hours for

    seizures, up to 8

    hours for

    sedation

    6 – 8 hours

    < 2 hour

    1-2 hour

    20-30 min

    Bioavailability

    100%

    83-100%

    100%

    90%

    44%

Evidence

    Author,

    year

    Design/ sample

    size

    Intervention & Comparison

    Outcome

    Klein

    2018

    Prospective

    observational

    study

    N=737

    • IM haloperidol 5 mg

    • IM ziprasidone 20 mg

    • IM olanzapine 10 mg

    • IM midazolam 5 mg

    • IM haloperidol 10 mg

    At 15 minutes, midazolam resulted in a greater

    proportion of patients adequately sedated

    (Altered Mental Status Scale <1) compared

    with all other drugs

    Martel,

    2005

    Prospective,

    double-blind,

    randomized

    N=201

    • IM droperidol 5 mg

    • IM midazolam 5 mg

    • IM ziprasidone 20 mg

    Adequate sedation was achieved at 15

    minutes in patients receiving midazolam

    compared to 30 minutes for droperidol and

    ziprasidone

Conclusions

  • Midazolam has a quick onset, reliable IM absorption, and evidence that supports its use an

    • effective pharmacologic agent for acute agitation which could lead clinicians to argue

    that midazolam is more efficacious than lorazepam for acute agitation.

References

    • Lorazepam. Micromedex [Electronic version].Greenwood Village, CO: Truven Health Analytics. Accessed 2020, February 24.

    http://www.micromedexsolutions.com/

    • Midazolam. Micromedex [Electronic version].Greenwood Village, CO: Truven Health Analytics. Accessed 2020, February 24.

    http://www.micromedexsolutions.com/

    • Nobay, et al. Acad Emerg Med. 2004;11(7):744-49.

    • Wyant M, et al. Psychopharmacol Bull 1990; 26:126 -9.

    • Meehan K, et al.. J Clin Psychopharmacol. 2001;21(4):389-397.

    • Battaglia J, et al. Am J Emerg Med. 1997;15(4):335-340.

    • Knott JC, et al. Ann Emerg Med. 2006;47(1):61-67.

    • Martel M, et al. Acad Emerg Med. 2006 Feb;13(2):233].

    • Klein LR, et al. Ann Emerg Med. 2018;72(4):374-385.

Tags:lorazepam midazolam acute agitation benzodiazepine

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Lorazepam vs Midazolam for Acute Agitation. Pharmacy Friday Pearls. jlp2.pdf