A 59-year-old woman underwent orthotopic heart transplantation 4 years earlier. At the time of transplantation, she was receiving pravastatin at a dose of 20 mg per day; she tolerated subsequent combination with immunosuppression (cyclosporine A, prednisone, mycophenolate mofetil) very well throughout the 4 years. After switching from pravastatin to simvastatin, she developed severe muscular weakness and laboratory evidence of muscle break down. Biochemical markers of rhabdomyolysis did not subside until after repeat hemodialysis and normalized after 2 months in conjunction with improved renal function. Clinical improvement was not apparent until after 5 months.