I don't know if this information is helpful, but my GI thought I was steroid dependant and wanted to put me on Imuran (I couldn't make the drop from 20mg to 15mg without flaring big time). Due to some family history and the potential side effects I resisted and asked if there was anything else we could try. He indicated that adding Xifaxin was new and had worked for some people. He was willing to let me try it to see if I could get off the pred without needing to go to another med. I am happy to report that I am down to 5mg of pred and continuing to taper. If I had to guess I'd say that he added the Xifaxin to help prevent or control the flares that were occurring when I tried to continue my taper. I had no breath test or known bacterial overgrowth, just an inability to get off pred and an extreme desire to not add any additional meds. So far it's working great. As I taper the pred I still have some side effects but they go away after a couple of days.
Diagnosed w/ severe pancolitis 11/20/2007
Asacol - 6 (400mg) 2x/day, Tums EX - 2 - 3x/day, Xifaxin 2 (200mg) 2x/day, Prednisone 5mg (started at 40mg), multi-vitamin, calcium and vit d supplement, potassium supplement, Junel FE (BCP)