J Am Acad Dermatol 71 (5): 941 - 947, 2014. doi: 10.1016 / j. jaad.2014.07.016 Key Points Drugs cause > 50% of Stevens-Johnson syndrome (SJS) and up to 95% of toxic epidermal necrolysis (TEN) cases, but infection, vaccination, and graft-vs-host disease are also potential causes.