Treatment of Small Intestinal Bacterial Overgrowth (SIBO)

Diagnosis and Treatment

The American Gastroenterological Association recommends glucose or lactulose breath tests as helpful non-invasive diagnostic tools for SIBO, though they require further standardization 1
Combined hydrogen and methane breath testing is more effective at identifying SIBO than hydrogen testing alone, according to the American Gastroenterological Association 1
The American College of Gastroenterology suggests that qualitative assessment for SIBO can be performed through small bowel aspirate, which should be coordinated with local microbiology services 1
Rifaximin is the first-line treatment for SIBO, with a recommended dosage of 550 mg twice daily for 1-2 weeks, effective in approximately 60-80% of patients with proven SIBO, as recommended by the American College of Gastroenterology 1

The American Gastroenterological Association recommends Rifaximin (550 mg twice daily for 1-2 weeks) as the preferred first-line treatment for SIBO, as it is not absorbed from the GI tract, reducing risk of systemic resistance 1
Doxycycline is an alternative antibiotic with similar efficacy to Rifaximin for SIBO treatment, according to the American College of Gastroenterology 1
Ciprofloxacin can be used as an alternative antibiotic for SIBO treatment, but with caution regarding tendonitis risk with long-term use, as recommended by the American Gastroenterological Association 2
Amoxicillin-clavulanic acid is an alternative antibiotic with similar efficacy to Rifaximin for SIBO treatment, according to the American College of Gastroenterology 1, 2

The American Gastroenterological Association recommends antidiarrheal medications such as loperamide or diphenoxylate for diarrhea associated with SIBO, preferred over codeine due to lower risk of dependence and sedation 2, 3
Bile acid sequestrants like cholestyramine or colesevelam can be used to manage bile salt malabsorption associated with SIBO, if tolerated, as recommended by the American College of Gastroenterology 2, 3
The American Gastroenterological Association suggests monitoring for vitamin D deficiency, which occurs in 20% of patients taking bile acid sequestrants, and checking for deficiencies in fat-soluble vitamins (A, E, K) in patients with SIBO 1

Rotating antibiotics are specifically recommended for SIBO treatment in patients with systemic sclerosis, according to the European League Against Rheumatism 4, 5
Antibiotics should be used cautiously in patients with preserved colon and short bowel syndrome to avoid disrupting energy salvage from bacterial fermentation, as recommended by the European Society for Clinical Nutrition and Metabolism 6
Metronidazole, amoxicillin-clavulanate, tetracycline, or non-absorbable antibiotics like rifaximin may be used in patients with short bowel syndrome, according to the American Gastroenterological Association 7
Antibiotics are recommended to treat intestinal bacterial overgrowth and reduce malabsorption in patients with chronic intestinal pseudo-obstruction, as recommended by the European Society for Clinical Nutrition and Metabolism 8

Lack of response to empirical antibiotics may be due to resistant organisms, SIBO not being present, or concurrent disorders, according to the American College of Gastroenterology 1
Long-term use of metronidazole can cause peripheral neuropathy, and patients should stop if numbness or tingling develops in feet, as recommended by the American Gastroenterological Association 2
Long-term ciprofloxacin use can cause tendonitis and rupture, and the lowest effective dose should be used, according to the American College of Gastroenterology 2
The American Gastroenterological Association recommends considering the risk of developing resistant organisms, including Clostridioides difficile, and using testing rather than empirical treatment whenever possible to help establish the cause for symptoms and support antibiotic stewardship 1, 2