What are the treatments for Small Intestine Bacterial Overgrowth (SIBO)?

From the Guidelines

Treatment for Small Intestinal Bacterial Overgrowth (SIBO) primarily involves antibiotics to reduce bacterial load, dietary modifications, and addressing underlying causes, with rifaximin being the most commonly prescribed antibiotic at 550 mg three times daily for 14 days, as recommended by the most recent and highest quality study 1. The most effective approach to managing SIBO involves a combination of antibiotics, dietary changes, and treatment of underlying conditions.

• Antibiotics: Rifaximin is often the first choice if it is on the local drug formulary, due to its minimal systemic absorption and effectiveness in reducing bacterial load 1.
• Alternative antibiotics include metronidazole, amoxicillin-clavulanate, doxycycline, and ciprofloxacin, which may be used in repeated courses every 2–6 weeks, often rotating to another antibiotic for a similar period of time before repeating 1.
• Dietary modifications: Following a low-FODMAP diet or an elemental diet can help reduce fermentable carbohydrates that feed bacteria, and provide pre-digested nutrients that are quickly absorbed before bacteria can utilize them 1.
• Treating underlying conditions: Addressing underlying causes such as adhesions, structural abnormalities, or motility disorders is crucial for long-term management, and prokinetic agents like low-dose erythromycin, prucalopride, or motegrity may help prevent recurrence by improving intestinal motility. It is essential to consider the risk of resistant organisms, including Clostridioides difficile, and the potential side effects of long-term antibiotic use, such as neuropathies associated with metronidazole 1.
• The use of probiotics has not been well-studied in the context of SIBO, and their effectiveness is uncertain 1.
• Cyclical antibiotic treatment or maintenance strategies combining dietary management and prokinetics may be necessary for some patients to prevent recurrence 1.

From the FDA Drug Label

To reduce the development of drug-resistant bacteria and maintain the effectiveness of neomycin sulfate tablets and other antibacterial drugs, neomycin sulfate tablets should be used only to treat or prevent infections that are proven or strongly suspected to be caused by susceptible bacteria Suppression of Intestinal Bacteria Neomycin sulfate tablets are indicated as adjunctive therapy as part of a regimen for the suppression of the normal bacterial flora of the bowel, e.g., preoperative preparation of the bowel.

• Neomycin sulfate is used as adjunctive therapy for the suppression of intestinal bacteria.
• The treatment for SIBO may include antibiotics such as neomycin sulfate to suppress the normal bacterial flora of the bowel 2.

From the Research

Treatments for SIBO

• Antibiotic therapy:
  • Rifaximin has been shown to be effective in treating SIBO, with a higher decontamination rate compared to metronidazole 3, 4, 5
  • Metronidazole is also used to treat SIBO, but has a lower efficacy rate compared to rifaximin 3
  • Norfloxacin is another antibiotic that has been shown to be efficacious in treating SIBO 4
• Alternative therapies:
  • Probiotics have been studied as a potential treatment for SIBO, with some studies showing promising results 6
  • Therapeutic diets, such as elemental diets, may also be effective in treating SIBO 6, 7
  • Herbal medicines have been used to treat SIBO, but more research is needed to confirm their efficacy 6

Treatment Approaches

• Elimination or modification of underlying causes: identifying and addressing underlying factors that contribute to SIBO, such as proton-pump inhibitors, opioids, or dysmotility 7, 4
• Induction of remission: using antibiotics, such as rifaximin, or elemental diets to eradicate bacteria in the small intestine 7, 4
• Maintenance of remission: using promotility drugs, dietary modifications, or repeat or cyclical antibiotics to prevent recurrence of SIBO 7