Some of the more common complaints that I see in my office patients are of bloating, abdominal discomfort, and excessive gas. Treating these patients is often very challenging, as these symptoms are very nonspecific and may be caused by many different problems. One of the more common causes, however, is a condition called SIBO. SIBO stands for Small Intestinal Bacterial Overgrowth. When SIBO is present, the levels of bacteria in the small intestine, which are normally very low, become significantly elevated. The excessive levels of bacteria will interfere with the normal digestive and absorptive processes of the small bowel. The nutrients which are normally broken down and absorbed by your gut are instead metabolized by the bacteria, producing excess gas, diarrhea, and pain. In severe cases patients may develop severe malabsorption with deficiencies in essential vitamins such as vitamin D and B12, fatty or greasy stools, and weight loss.
Many different conditions can lead to SIBO, such as diabetes, prior bowel surgery, Crohn’s disease, lack of stomach acid, and aging to name a few. I suspect it in any patient with chronic abdominal pain, bloating, gas, or diarrhea whether or not they have an obvious predisposing condition. If suspected, SIBO can be tested for in my office. We use a procedure called a breath test to make the diagnosis. Breath testing is based on the fact that when gut bacteria break down carbohydrates, gases such as hydrogen and methane are produced. These can be detected by measuring their levels in the exhaled breath. We administer a test amount of a carbohydrate such as glucose and then measure the hydrogen and methane produced over the next two hours. If elevated levels are found, then the patient has SIBO. The test is completely noninvasive, painless, and safe.
Once SIBO is found, it can be treated. The most effective treatment is with a course of an antibiotic. I prefer to use a medication called rifamixin, which is very safe, effective, and has few side effects. A ten day course is typically given, which can usually produce long lasting improvement. Sometimes stopping medications that reduce stomach acid or administering pancreatic enzyme supplements can be helpful as well. But unless SIBO is suspected and tested for, it can’t be helped.