Irritable bowel syndrome can make life miserable, although doctors often find nothing obvious wrong with a sufferer’s digestive tract. A person with IBS may have embarrassing bouts of urgent diarrhea that can make her reluctant to get very far from a toilet. Others may have chronic constipation that can be very difficult to overcome. The doctor’s pronouncement that this is a “functional” digestive disorder-with the implication that it is psychosomatic-just adds insult to injury. What can be done for IBS with diarrhea?
Is Xifaxan the Best Treatment?
Q. Recently my doctor prescribed Xifaxan for IBS with diarrhea (IBS-D). I was excited to have a cure, but when I picked up my prescription and learned about all the side effects, particularly death and the fact that this drug could cause diarrhea weeks or months after the course of treatment, I refused to take it.
After suffering with this condition for years, I am now wondering if I made the right decision.
A. Xifaxan (pronounced zi-FAX-an) is being heavily advertised for irritable bowel syndrome with diarrhea (IBS-D). This antibiotic (rifaximin) can cause side effects such as nausea and liver enzyme elevation. It has been shown to be more effective than placebo, with 40% of the patients getting rifaxamin reporting symptom control compared to 31% of those given placebo (Pharmacotherapy, March, 2016).
Because rifaxamin changes the balance of bacteria in the digestive tract, it can result in Clostridium difficile overgrowth. This might well lead to hard-to-control diarrhea. C. diff. colitis sometimes leads to death.
We can’t say if you made the right decision, but we can’t fault you for being cautious.
What Causes IBS with Diarrhea?
Rather than being a psychosomatic condition, there is evidence that IBS with diarrhea may result from bacterial toxins and their effect on the nerves that serve the digestive tract (PLOS One, May 13, 2015). Small intestine bacterial overgrowth, or SIBO, has been associated with IBS-D (World Journal of Gastroenterology, Jan. 28, 2016). In addition, research has shown that there are variations in the types of microbes that inhabit the digestive tracts of people with IBS-D compared to those of healthy individuals (IUBMB Life, online March 26, 2016).
The presumed connection with an altered bacterial ecology in the digestive tract explains why using an antibiotic such as rifaximin that works right in the gut might be helpful. There may be other ways to manage your IBS with diarrhea, however. A recent review suggests that taking prebiotics and eating a diet that restricts fermentable carbohydrates (a low FODMAP diet) may be able to shift the microbiome and alleviate symptoms (Proceedings of the Nutrition Society, online Feb. 24, 2016).
You may also be interested in our hour-long interview with Gerald Mullin, MD, MS, CNSP, of Johns Hopkins University and Norman Robillard, PhD. Dr. Mullin’s book is The Gut Balance Revolution and Dr. Robillard’s book is Fast Tract Digestion IBS.