What is the main cause of Stevens Johnson Syndrome (SJS) and toxic epidermal necrolysis (TEN)?

Stevens Johnson Syndrome (SJS) and toxic epidermal necrolysis (TEN) are primarily caused by severe reactions to medications. Certain drugs, particularly allopurinol, sulfonamides, anticonvulsants, and non-steroidal anti-inflammatory drugs, have been implicated as common triggers for these conditions. The immune system's response leads to extensive skin and mucous membrane damage, characteristic of SJS and TEN.

While infections, genetic predispositions, and environmental factors can contribute to the risk of developing skin conditions, they are not the main causative factors for SJS and TEN. SJS and TEN are distinctly associated with drug reactions, making this the most significant cause to understand in the context of diagnosis and prevention. Recognizing the role of specific medications is crucial, as it informs the management of patients at risk and helps in the timely identification necessary to mitigate severe outcomes.