Toxic epidermal necrolysis (TEN) is a rare but life-threatening disorder of children and adults in which the skin peels off in sheets and mucosal surfaces slough. It is best viewed as a severe from of erythema multiforme, with even more extreme involvement than one sees with the Stevens-Johnson syndrome (SJS). However, the distinction between TEN and SJS is not clear, as there are a number of overlapping definitions. TEN usually represents an idiosyncratic hypersensitivity to a medication, but may result from a variety of infections, or have no clear linkage. Sulfonamide antibiotics, barbiturates, carbamazepine, and allopurinol seem to be the most common offending agents. TEN usually has an acute onset one to three weeks after ingestion of the offending drug. TEN requires distinction from staphylococcal scalded skin syndrome, as treatment is different.