Pathways of drug metabolism

  • G. Gordon Gibson
  • Paul Skett


The routes by which drugs may be metabolised or biotransformed are many and varied and include the chemical reactions of oxidation, reduction, hydrolysis, hydration, conjugation and condensation. It is important that these pathways are studied as the route of metabolism of a drug can determine whether it shows any pharmacological or toxicological activity. Drug metabolism is normally divided into two phases, phase I (or functionalisation reactions) and phase II (or conjugative reactions). The chemical reactions normally associated with phase I and phase II drug metabolism are given in Table 1.1.


Drug Metabolism Xanthine Oxidase Endogenous Compound Diamine Oxidase Conjugation Reaction 
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Further reading

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Copyright information

© Springer Science+Business Media Dordrecht 1996

Authors and Affiliations

  • G. Gordon Gibson
    • 1
  • Paul Skett
    • 2
  1. 1.School of Biological SciencesUniversity of SurreyUK
  2. 2.University of GlasgowUK

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