I was on it for several months. A combination of rifaximin and other meds helped me get better after the first time I was hospitalized - at that point I couldn't eat, and the rifaximin and entocort helped.
That said, the med is really, really expensive. It was over a $1000 for a month's worth. Maybe even $2k. I have insurance, but my copay was still super high and my dr. had to write a note before my insurance would cover it.
I didn't notice any side effects from it. Good luck with your decision!