Dermatological Adverse Drug Reactions

Skin is one of the organs most frequently affected by side effects of drugs, with a huge variety of phenotypes from mild maculopapular eruptions or urticaria to life-threatening reactions such as DRESS or epidermal necrolysis (Stevens–Johnson syndrome or toxic epidermal necrolysis). This chapter will focus on the clinical differences between the many “phenotypes” of dermatological adverse drug reactions, because they imply different mechanisms, severity, and risk factors, even when the offending drug is the same. Furthermore, recent advances suggest that distinct phenotypes may be related to specific genetic background, in relation to the polymorphism of the human leukocyte antigen system.