Rifguard contains Rifaximin. It is used to inhibit bacterial growth and treats Irritable Bowel Syndrome with Diarrhea. Rifaximin medicines are manufactured by Heterohealthcare.com. Rifguard contains Rifaximin. It is used to inhibit bacterial growth and treats Irritable Bowel Syndrome with Diarrhea. Rifaximin medicines are manufactured by Heterohealthcare.com