Background: It is routine practice to discontinue corticosteroids or at least reduce the dose to ≤20 mg/day in patients being considered for lung transplantation. No studies have either evaluated the risks of pre-transplantation steroid use or determined safe or optimal doses in the pre- or post-lung transplantation time frame. We sought to determine whether there are deleterious effects of prednisone administration before lung transplantation and if corticosteroids affect survival after lung transplantation. Methods: Between November 1990 and January 2005, 201 patients underwent lung transplantation. Of these, 126 patients had been prescribed prednisone before lung transplantation. Sixty-four had taken low-dose (LD) prednisone (<0.42 mg/kg/m2 per day), and 62 had taken high-dose (HD) prednisone (≥0.42 mg/kg/m2 per day). The LD Group also included 75 patients never prescribed steroids before lung transplantation (n = 139). Results: A comparison of survival rates between LD and HD Cohorts showed better survival in the LD group, p value by log rank for LD vs HD <0.01. Other than having more emphysema patients (53/139, 40%) and fewer idiopathic pulmonary fibrosis patients (21/139, 16%) in the LD group (p < 0.01), pre-transplantation characteristics between the 2 cohorts were similar. In addition, the LD Group had more bilateral lung recipients (p < 0.01). During the first 100 days after transplantation, 20 HD (20/62) patients and 16 LD (16/139) died (p < 0.01). Conclusions: Survival in the LD Cohort was strikingly better than for patients receiving ≥0.42 mg/kg/m2 per day. Deaths in the early post-operative period for the HD Group may be related to steroid-induced complications such as poor wound healing and serious infections. A pre-lung transplantation steroid dose adjusted for body mass index of ≥0.42 mg/kg/m2 per day may be associated with increased complications and worse survival after lung transplantation. Further studies are warranted to confirm these results. Copyright © 2006 by the International Society for Heart and Lung Transplantation.