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CYP2D6 phenotyping with dextromethorphan

Anna Wojtczak1, Mariola Rychlik-Sych, Eliza Krochmalska-Ulacha

  • 1Department of Pharmacogenetics, Medical University of Łódź, Muszyńskiego 1, PL 90-151 Łódź, Poland. awojt@mp.pl

Pharmacological Reports : PR
|January 16, 2008
PubMed

Insights

This study determined the CYP2D6 oxidation phenotype in Polish individuals using dextromethorphan. The frequency of poor metabolizers (PMs) was 9.4%, aligning with other Caucasian populations.

Area of Science:

  • Pharmacogenomics
  • Drug Metabolism

Background:

  • Genetic variations influence drug oxidation, impacting pharmacotherapy efficacy and safety.
  • Cytochrome P450 2D6 (CYP2D6) phenotype determination is crucial for personalized medicine.
  • Understanding individual drug metabolism aids in preventing adverse drug reactions and optimizing treatment.

Purpose of the Study:

  • To identify the CYP2D6 oxidation phenotype in a healthy Polish population.
  • To utilize dextromethorphan (DM) as a probe drug for CYP2D6 phenotyping.
  • To establish the frequency of different CYP2D6 metabolic phenotypes in the studied cohort.

Main Methods:

  • A study involving 85 healthy adult volunteers of Polish origin.
  • Oral administration of 40 mg dextromethorphan (DM) followed by 10-hour urine collection.
  • Analysis of DM and its metabolite dextrorphan (DX) using High-Performance Liquid Chromatography (HPLC).
  • Phenotyping based on the metabolic ratio (MR) of urinary DM/DX output.

Main Results:

  • The metabolic ratio (MR) was calculated to classify individuals as extensive metabolizers (EM) or poor metabolizers (PM).
  • Individuals with a dextromethorphan MR > 0.3 were classified as PMs.
  • The frequency of the poor metabolizer (PM) phenotype was found to be 9.4% in the Polish cohort.

Conclusions:

  • The prevalence of CYP2D6 poor metabolizers in the Polish population is 9.4%.
  • This frequency is consistent with the reported range (3-10%) observed in other Caucasian populations.
  • These findings contribute to understanding pharmacogenetic variations relevant to drug therapy in this demographic.

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