Nafcillin is an antibiotic used for infections due to penicillin-resistant Staphylococcus aureus. In general, the adverse reactions to nafcillin have not been frequent and serious. We report here a new type of adverse reaction to nafcillin in a patient with end-stage renal disease in whom nafcillin caused the unexpected complication of bullous drug eruption and subseqent neutropenia. Three weeks after the start of intravenous nafcillin for the treatment of peritoneal dialysis peritonitis, the patient developed blisters on his right ankle. These became progressive and widespread, with bullae affecting most of the body surface. In addition, neutropenia developed three days after the appearance of bullous skin lesions. Spontaneous recovery of skin lesions and neutropenia was observed after the withdrawal of naficillin. When treating patients with chronic renal failure, physicians should be aware of these rare but potentially severe adverse reactions.