Elsevier

Life Sciences

Volume 66, Issue 9, 21 January 2000, Pages PL133-PL139
Life Sciences

Pharmacology letter accelerated communication
Effect of St. John's wort (Hypericum perforatum) on cytochrome P-450 2D6 and 3A4 activity in healthy volunteers

https://doi.org/10.1016/S0024-3205(99)00659-1Get rights and content

Abstract

The effects of the herb St. John's wort (Hypericum perforatum), a purported antidepressant, on the activity of cytochrome P-450 (CYP) 2D6 and 3 A4 was assessed in seven normal volunteers. Probe substrates dextromethorphan (2D6 activity) and alprazolam (3 A4 activity) were administered orally with and without the co-administration of St. John's wort. Urinary concentrations of dextromethorphan and dextrorphan were quantified and dextromethorphan metabolic ratios (DMRs) determined. Plasma samples were collected (0–60 hrs) for alprazolam pharmacokinetic analysis sufficient to estimate tmax, Cmax, t12 and AUC. Validated HPLC methods were used to quantify all compounds of interest. No statistically significant differences were found in any estimated pharmacokinetic parameter for alprazolam or DMRs. These results suggest that St. John's wort, when taken at recommended doses for depression, is unlikely to inhibit CYP 2D6 or CYP 3A4 activity.

References (20)

  • R.L. Miller et al.

    J Chromatogr

    (1988)
  • D.M. Eisenberg et al.

    JAMA

    (1998)
  • D.A. Bennet et al.

    Ann Pharmacother

    (1998)
  • H.J. Kim et al.

    Plant Medica

    (1997)
  • J.Z. Shi et al.

    Acta Pharmacologica Sinica

    (1996)
  • Y.N. Cai et al.

    Carcinogenesis

    (1997)
  • M.T. Obermeier et al.

    Xenobiotica

    (1995)
  • H.R. Ha et al.

    Eur J Clin Pharmacol

    (1995)
  • J.M. Lasker et al.

    J Pharmacol Exp Ther

    (1984)
  • Y. Li et al.

    Drug Metab Dispos

    (1994)
There are more references available in the full text version of this article.

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