From the Guidelines
Small Intestinal Bacterial Overgrowth (SIBO) should be treated with rifaximin (Xifaxan) as the first-line option at 550 mg three times daily for 14 days, as it is the most effective treatment according to the latest evidence 1.
Treatment Options
- Alternative antibiotics include neomycin (500 mg twice daily), metronidazole (250 mg three times daily), or ciprofloxacin (500 mg twice daily), all for 10-14 days.
- For methane-predominant SIBO, a combination of rifaximin and neomycin is often more effective.
- Dietary modifications are also important, with a low-FODMAP diet being beneficial during treatment, as it restricts fermentable carbohydrates that feed bacteria 1.
Prevention of Recurrence
- Prokinetic agents like low-dose erythromycin (50-100 mg at bedtime) or prucalopride (0.5-2 mg daily) can help prevent recurrence by improving intestinal motility.
- Addressing underlying causes such as adhesions, motility disorders, or anatomical abnormalities is crucial for long-term management.
Pathophysiology
- SIBO occurs when normal protective mechanisms fail, allowing bacteria from the colon to colonize the small intestine where they interfere with nutrient absorption and produce gas through fermentation of food 1.
- The condition is often associated with symptoms like bloating, gas, diarrhea, and abdominal pain.
Importance of Treatment
- SIBO can lead to malabsorption, abdominal discomfort, diarrhoea, constipation, flatulence, and bloating, which can significantly impact a patient's quality of life 1.
- Treatment of SIBO is essential to prevent long-term complications and improve patient outcomes.
Recent Studies
- A recent study published in 2020 found that rifaximin is often the first choice for treating SIBO if it is on the local drug formulary 1.
- Another study published in 2013 highlighted the importance of understanding the mechanisms through which host-microbiota interactions underlie pathophysiology and generate symptoms in patients with functional bowel disorders, including SIBO 1.
From the Research
Definition and Diagnosis of SIBO
- Small intestinal bacterial overgrowth (SIBO) is a condition where there is an excessive growth of bacteria in the small intestine 2.
- The current accepted criteria for the diagnosis of SIBO is the presence of coliform bacteria isolated from the proximal jejunum with >10(5) colony-forming units/mL 2.
- SIBO can be diagnosed using breath testing, such as the glucose breath test or lactulose breath testing (LBT) 3, 4, 5.
Treatment of SIBO
- Broad-spectrum antibiotics are the first-line treatment for SIBO, but they can have significant side effects and SIBO often recurs after treatment 6.
- Rifaximin is a commonly used antibiotic for the treatment of SIBO, and has been shown to be effective in normalizing breath test results and improving symptoms 3, 4, 5.
- Herbal therapies have also been shown to be effective in treating SIBO, and may be a useful alternative to antibiotics 5.
- Other alternative therapies, such as probiotics and therapeutic diets, may also be useful in managing SIBO, but more research is needed to fully understand their effectiveness 6.
Comparison of Treatment Options
- Rifaximin has been compared to metronidazole in the treatment of SIBO, and has been shown to have a higher decontamination rate and better tolerability 4.
- Herbal therapy has been compared to rifaximin, and has been shown to be at least as effective in resolving SIBO by LBT 5.
- The use of alternative therapies, such as herbal remedies and probiotics, may be a useful adjunct to antibiotic treatment, and may help to reduce the risk of recurrence 6, 5.