Rifaximin (Xifaxan), a common antibiotic in the treatment of travelers' diarrhea, appears to have a benefit for those who suffer from irritable bowel syndrome (IBS), according to two studies published in the New England Journal of Medicine. In the studies, 1,200 IBS sufferers took rifaximin or a placebo (sugar pill) three times a day for two weeks. The findings show that approximately 40 percent of the patients who took the antibiotic had reduced symptoms of bloating, abdominal pain, and loose stools for at least two weeks during the subsequent month, compared with the slightly less than one-third of the patients taking the placebo. None of the volunteers in the study suffered from constipation. The studies were funded by the drug's manufacturer, Salix Pharmaceuticals.

What makes rifaximin especially appealing for IBS sufferers is that the drug doesn't appear to foster resistance among gut bacteria, so it can be used repeatedly, a big plus for sufferers of a chronic disease. And although the percentage of patients who responded favorably to the drug was relatively small, physicians say that rifaximin at least gives them an additional therapy to offer patients with few options.

But both physicians and IBS patients may have to wait a while for the drug's availability. In March 2011, the FDA declined approval for rifaximin for IBS symptoms, citing that it needed more data from the manufacturer on how the medication should be used in treating patients with recurrent symptoms. Salix Pharmaceuticals has said it would request a meeting with FDA officials to discuss how it should proceed.

Finding Relief

Irritable bowel syndrome is a common disorder that affects the large intestine, causing a myriad of symptoms, including cramping, abdominal pain, bloating, gas, diarrhea, and constipation. In many cases, IBS symptoms can be controlled by managing your diet, lifestyle, and stress. Talk with your doctor about determining the best course of action for you. These tips may also help:

  • Avoid problem foods, including alcohol, chocolate, caffeinated beverages such as coffee and sodas, dairy products, beans, cabbage, and fatty foods.
  • Drink plenty of fluids daily; water is best.
  • Exercise regularly-about 30 minutes on most days of the week-to help relieve stress and stimulate normal contractions of your intestines. If you've been inactive or have other medical problems, be sure to check with your doctor to determine the type and how much exercise is right for you.