Study of urinary 6 beta-hydroxycortisol/cortisol ratio in spot urine sample as a biomarker of 3A4 enzyme activity in healthy and epileptic subjects of Egyptian population

Pharmacol Res. 2005 Jun;51(6):575-80. doi: 10.1016/j.phrs.2005.02.014.


The ratio of urinary 6 beta-hydroxycortisol/cortisol (6 beta-OHC/FC) in morning spot urine samples collected from 8:00 a.m. to 12:00 p.m. was studied using ELIZA kits (Stabiligen) in a group of healthy adult Egyptians (control group) of both sex (n=65, age range: 16-48 years). The frequency distribution of urinary 6 beta-OHC/FC ratio was widely distributed among subjects with higher values in males in comparison to females. No bimodality in either sex was observed. Another group of adult epileptic patients (n=16) was studied for the influence of chronic carbamazepine antiepileptic drug administration on urinary 6 beta-OHC/FC ratio in spot urine samples. The induction property of carbamazepine on CYP3A4 was observed through significant increase (p=0.01) in 6 beta-OHC/FC ratio among epileptic patients in comparison with control subjects. In conclusion, the frequency distribution of urinary 6 beta-OHC/FC ratio among Egyptians shows sexual dimorphism. Also, measurement of urinary 6 beta-OHC/FC ratio provides a simple non-invasive method to monitor CYP3A4 enzyme induction during administration of carbamazepine antiepileptic drug.

Publication types

  • Comparative Study

MeSH terms

  • Adolescent
  • Adult
  • Biomarkers / urine
  • Cytochrome P-450 CYP3A
  • Cytochrome P-450 Enzyme System / urine*
  • Egypt
  • Enzyme Activation / physiology
  • Epilepsy / enzymology*
  • Epilepsy / urine*
  • Female
  • Humans
  • Hydrocortisone / analogs & derivatives*
  • Hydrocortisone / urine*
  • Male
  • Middle Aged
  • Regression Analysis


  • Biomarkers
  • 6 beta-hydroxycortisol
  • Cytochrome P-450 Enzyme System
  • CYP3A protein, human
  • Cytochrome P-450 CYP3A
  • CYP3A4 protein, human
  • Hydrocortisone