Abstract: A method for preventing tissue damage associated with graft-versus-host disease in a patient having undergone hematopoietic cell transplantation, and host-versus-graft disease in a patient having undergone organ allograft transplantation. The method includes orally administering to the patient a prophylactically effective amount of a topically active corticosteroid, such as beclomethasone dipropionate, for a period of time following hematopoietic cell or organ allograft transplantation, and prior to the presentation of symptoms associated with graft-versus-host disease or host-versus-graft disease. Representative tissues includes tissue of the intestine and liver, while representative tissue damage includes inflammation thereof.