UMEM Educational Pearls

Category: Toxicology

Title: All Benzodiazepines are Metabolized by the Liver

Keywords: benzodiazepine, lorazepam, liver (PubMed Search)

Posted: 11/11/2013 by Bryan Hayes, PharmD (Emailed: 11/14/2013) (Updated: 11/14/2013)
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All benzodiazepines are metabolized by the liver. Some are just metabolized by pathways that are less dependent on global liver function.

The ‘LOT’ drugs are metabolized by conjugation, have no active metabolites, and have minimially affected half-lives even in the setting of liver disease.

  • L – Lorazepam

  • O – Oxazepam

  • T – Temazepam

The rest of the benzodiazepines are primarily metabolized via hepatic CYP-mediated oxidation and may have prolonged duration of effect in patients with marked liver impairment.

For a bit more detail and commentary by Dr. David Juurlink, please read my recent post on the Academic Life in Emergency Medicine blog: http://academiclifeinem.com/all-benzodiazepines-are-metabolized-by-the-liver/

References

Mihic SJ, Harris RA. Chapter 17. Hypnotics and Sedatives. In: Chabner BA, Knollmann BC, eds. Goodman & Gilman's The Pharmacological Basis of Therapeutics. 12nd ed. New York: McGraw-Hill; 2011. http://www.accesspharmacy.com/content.aspx?aID=16663643. Accessed November 7, 2013.

Lee DC, Ferguson KL. Chapter 74. Sedative-Hypnotics. In: Lee DC, Ferguson KL, eds.Goldfrank's Toxicologic Emergencies. 9th ed. New York: McGraw-Hill; 2011. http://www.accesspharmacy.com/content.aspx?aID=6520459. Accessed November 7, 2013.

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