There have been several reviews recently on the efficacy of antibiotics in Crohn's disease, and no text on inflammatory bowel disease is complete without a chapter that addresses this issue. This is perhaps an unanticipated sequel to theMycobacterium paratuberculosis story of the 1980s, because prior to that putative viruses held our attention and antibiotics were seldom considered. The M paratuberculosis initiative prompted renewed use of antituberculosis regimens—some of which succeeded some of the time—and there followed a notion that if combinations of antituberculosis antibiotics were beneficial, maybe other broad spectrum antibiotics would be as well. Those who wish to make judgements about drug dose, duration, etc, for the various forms of Crohn's disease may consult recent reviews …