Reasons for adverse outcomes of infectious diseases are always under scrutiny. We expect infectious illnesses to have a specific course and outcome. Outcomes outside of the expected range are unacceptable, although the natural course of each infection includes them. Adverse outcomes that are products of medical invention are of particular import because they imply changes inpractice. One such situation is corticosteroid-induced fatal or severe varicella-zoster virus (VZV) infections. This topic, although not new, has received considerable interest because of recent warnings by the Food and Drug Administration.1 Case reports, retrospective studies, and reviews that have appeared since the 1950s suggest that high-dose (<1 to 2 mg/kg per day) but not low-dose (5 to 20 mg/day) systemic use of corticosteroids in both immunocompetent and particularly in immunosuppressed patients may be associated with severe or fatal outcome, particularly if the drugs are given immediately prior to or during the incubation period.