Question: xifaxan how long to work?
Answer: 2 Weeks of Antibiotic Therapy Relieves IBS. Jan. 5, 2011 -- A two-week course of the antibiotic rifaximin (Xifaxan) helps to relieve the symptoms of irritable bowel syndrome (IBS), and the relief lasts up to 10 weeks after stopping the medication, according to new research.