Skin as a Portal of Entry for Systemic Effect: Xenobiotic Metabolism

  • David R. Bickers
  • Hasan Mukhtar
Part of the NATO ASI Series book series (NSSA, volume 181)


The body possesses three major portals of entry for environmental agents and these include the skin, the gastrointestinal tract and the respiratory tree. In the past, most pharmaceutical research focused on the oral or parenteral administration of drugs since it was believed that the skin was practically impermeable to such agents. In fact, virtually all drugs applied to the skin were, until recent years, designed only to treat dermatologic diseases involving this tissue and not for systemic effects. However, in recent years, there has been renewed interest in considering the skin as a potential portal of entry for pharmacologic agents. The concept of transdermal drug delivery involves the development of self-contained discrete dosage forms which, when applied to intact skin, deliver the drug(s) through the skin at a controlled rate to the systemic circulation. (Monkhouse and Huq, 1988) The devices currently employed for this approach usually consist of an outer impermeable barrier covering, beneath which is a reservoir of drug with a rate-controlling membrane, contact adhesive and a protective wrapper that is removed prior to application to the skin.


Hair Follicle Sebaceous Gland Epoxide Hydrolase Xenobiotic Metabolism Mixed Function Oxidase 
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Copyright information

© Plenum Press, New York 1990

Authors and Affiliations

  • David R. Bickers
    • 1
  • Hasan Mukhtar
    • 1
  1. 1.Department of DermatologyCase Western Reserve UniversityClevelandUSA

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