[Acute life-threatening drug reactions of the skin].

Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are acutely occurring, unpredictable, often life-threatening reactions that are a huge challenge in clinical practice. They are characterized by extensive blistering of skin and mucosa and are considered as one disease entity of different severity. Thus, they are summarized as SJS/TEN or EN (for epidermal or epithelial necrolysis). The diagnosis can be confirmed through synopsis of clinical pattern and histopathological findings. To identify the inducing factors, it is crucial to obtain a detailed and thorough medication and infection history. Based on the results of large epidemiological studies, potentially inducing drugs can be narrowed down even in cases of multimedication and underlying diseases. Agents with a high risk for SJS/TEN are allopurinol, antibacterial sulfonamides, non-steroidal anti-inflammatory drugs of the oxicam-type, various antiepileptics and nevirapine. They alone explain more than half of the cases of SJS/TEN. Typically, the reaction occurs during the first continuous use of the medication, while the beginning of use most often is one to four weeks prior to reaction onset. However, a drug is not always the cause of the reaction, but in approximately 70-75% of the cases very likely. In other cases infections may be potential causes. If certain medications are thought to be the inducing factors, they should be withdrawn without delay. In addition, symptomatic treatment should be initiated. In case of progression, an additional immunomodulating therapy should be considered. In this respect, systematic reviews have shown best results for cyclosporine A and systemic steroids.