American Journal of Clinical Dermatology

, Volume 4, Issue 9, pp 623–639 | Cite as

Drug Interactions of Clinical Significance for the Dermatologist

Recognition and Avoidance
  • Lori E. Shapiro
  • Sandra R. Knowles
  • Neil H. Shear
Review Article


While it would be impossible for any dermatologist to remember all potential drug interactions, knowledge of the mechanisms of drug interactions can help reduce the risk of serious adverse outcomes. Most drugs are associated with interactions but the majority do not produce significant outcomes. Dealing with drug interactions is a challenge in all clinical practice, including dermatology. New information continues to appear, and dermatologists need to know about the drugs they use.

This article focuses on the mechanisms of drug interactions. In particular, the life of a drug in terms of absorption, distribution, metabolism and excretion are reviewed with the focus on points of importance and relevance to drug interactions. The most clinically important drug interactions in dermatological practice are caused by alterations in drug metabolism. The contributions of P-glycoprotein, pharmacogenetic variation and genetic polymorphisms to drug interactions are highlighted, and the best evidence for drug interactions involving drug classes relevant to the dermatologist is presented.

Since the initial evidence for clinically relevant drug interactions comes from case reports, prescribing physicians can have a major role in collating information on interactions. By understanding the mechanisms behind drug interactions and staying alert for toxicities, we can help make drug therapy safer and reduce the fear of drug interactions.


Drug Interaction Fluconazole Itraconazole Clarithromycin Ketoconazole 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



No sources of funding were used to assist in the preparation of this manuscript. The authors have no conflicts of interest that are directly relevant to the content of this manuscript.


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Copyright information

© Adis Data Information BV 2003

Authors and Affiliations

  • Lori E. Shapiro
    • 1
    • 2
    • 3
    • 4
  • Sandra R. Knowles
    • 3
  • Neil H. Shear
    • 1
    • 2
    • 3
    • 4
    • 5
  1. 1.Division of Clinical PharmacologySunnybrook and Women’s College Health Science Centre and the University of TorontoTorontoCanada
  2. 2.Division of DermatologySunnybrook and Women’s College Health Science Centre and the University of TorontoTorontoCanada
  3. 3.Drug Safety ClinicSunnybrook and Women’s College Health Science Centre and the University of TorontoTorontoCanada
  4. 4.Department of MedicineSunnybrook and Women’s College Health Science Centre and the University of TorontoTorontoCanada
  5. 5.Department of PharmacologySunnybrook and Women’s College Health Science Centre and the University of TorontoTorontoCanada

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