Severe cutaneous adverse drug reactions

Drug eruptions are among the most common diseases of the skin. The majority of cases are benign and self-limited, however particular variants are very severe and potentially life threatening. A precise and rapid diagnosis is essential but can be difficult in some instances as drug eruptions may lack specific histological criteria. Furthermore, pitfalls in the diagnosis are frequent and heightened awareness to the possible mimicry of other skin diseases is required. This article focuses on three particularly dangerous forms of cutaneous adverse reactions, namely acute generalized exanthematous pustulosis, drug reaction with eosinophilia and systemic symptoms, Stevens-Johnson syndrome and toxic epidermal necrolysis. As histological assessment alone may be insufficient to establish the diagnosis, special attention is also paid to clinical features and differential diagnosis.