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British Journal of Clinical Pharmacology logoLink to British Journal of Clinical Pharmacology
. 1989 May;27(5):634–637. doi: 10.1111/j.1365-2125.1989.tb03429.x

Extra-hepatic metabolism of midazolam.

G R Park 1, A R Manara 1, S Dawling 1
PMCID: PMC1379932  PMID: 2667600

Abstract

Six patients received 10 mg of midazolam intravenously during the anhepatic period of liver transplantation. Arterial blood was sampled during this time and for a similar period following revascularisation. The plasma was analysed using gas chromatography and electron capture detection (GC-ECD) for midazolam alpha-hydroxymidazolam and alpha-hydroxymidazolam glucuronide. Five of the six patients had small but significant concentrations of metabolites detected during the anhepatic period, demonstrating the presence of extra-hepatic sites of metabolism for this drug. The remaining patient had plasma concentrations of metabolites below the lower limit of detection (2 micrograms l-1). This may represent a pharmacogenetic abnormality or a temporary failure of midazolam metabolism secondary to the patients illness affecting the extra-hepatic sites of metabolism.

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Selected References

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