Toxic epidermal necrolysis (TEN), or Lyell's syndrome, is a fulminant bullous dermatitis. TEN is often a drug-induced reaction and virtually any drug class appears capable of provoking it. We report here a case of TEN after administration of ciprofloxacin. Systemic lupus erythematosus (SLE) was suspected as a possible etiologic or modifying cofactor in TEN in this case.