Toxic epidermal necrolysis (TEN) and Stevens-Johnson syndrome (SJS) are life-threatening diseases characterized by extensive epidermal destruction. The aim of our study was to investigate apoptosis in keratinocytes of patients with TEN and TEN/SJS overlap syndrome. Keratinocytes from TEN patients were found to undergo extensive apoptosis. These results suggest that cell destruction in TEN occurs as a result of apoptosis. Our findings suggest that apoptosis inhibitory agents may play an important part in the therapeutic strategy of TEN.