Small intestinal bacterial overgrowth: Management
- Mark Pimentel, MD, FRCP(C)
Mark Pimentel, MD, FRCP(C)
- Executive Director
- Medically Associated Science and Technology (MAST) Program
- Cedars-Sinai Medical Center
Small intestinal bacterial overgrowth (SIBO) is a condition in which the small bowel is colonized by excessive aerobic and anaerobic microbes that are normally present in the colon. The majority of patients with SIBO present with bloating, flatulence, abdominal discomfort, or diarrhea. This topic will review the management of SIBO. The etiology, pathogenesis, clinical manifestations, and diagnosis of SIBO are presented separately. (See "Small intestinal bacterial overgrowth: Clinical manifestations and diagnosis".)
The mainstay of therapy for SIBO are antibiotics to reduce (rather than eradicate) small intestinal bacteria. In addition, some patients require treatment of underlying nutritional deficiencies and associated ileitis/colitis.
Antibiotic therapy — Antibiotic therapy is typically begun on an empiric basis. The selection of antimicrobial regimens is based on the pattern of bacterial overgrowth, the prevalence of risk factors for drug-resistance (recent or repeated prior exposure), relevant antibiotic allergies, and cost . It is unnecessary to repeat breath testing if symptoms resolve with treatment. (See "Small intestinal bacterial overgrowth: Clinical manifestations and diagnosis", section on 'Carbohydrate breath test'.)
●Hydrogen-predominant bacterial overgrowth — In patients with hydrogen predominant bacterial overgrowth without excess methane production, we use rifaximin (1650 mg/day for 14 days). Rifaximin is nonabsorbable rifamycin derivative. It is well tolerated and has been demonstrated to be effective in the treatment of SIBO [2-8]. However, the high cost of rifaximin has limited its use.
●Methane-predominant bacterial overgrowth — In patients with methane-predominant bacterial overgrowth, we use a combination of neomycin 500 mg twice daily and rifaximin 550 mg three times daily for 14 days .To continue reading this article, you must log in with your personal, hospital, or group practice subscription. For more information on subscription options, click below on the option that best describes you:
- Singh VV, Toskes PP. Small Bowel Bacterial Overgrowth: Presentation, Diagnosis, and Treatment. Curr Treat Options Gastroenterol 2004; 7:19.
- Quigley EM, Abu-Shanab A. Small intestinal bacterial overgrowth. Infect Dis Clin North Am 2010; 24:943.
- Shah SC, Day LW, Somsouk M, Sewell JL. Meta-analysis: antibiotic therapy for small intestinal bacterial overgrowth. Aliment Pharmacol Ther 2013; 38:925.
- Attar A, Flourié B, Rambaud JC, et al. Antibiotic efficacy in small intestinal bacterial overgrowth-related chronic diarrhea: a crossover, randomized trial. Gastroenterology 1999; 117:794.
- Tahan S, Melli LC, Mello CS, et al. Effectiveness of trimethoprim-sulfamethoxazole and metronidazole in the treatment of small intestinal bacterial overgrowth in children living in a slum. J Pediatr Gastroenterol Nutr 2013; 57:316.
- Bouhnik Y, Alain S, Attar A, et al. Bacterial populations contaminating the upper gut in patients with small intestinal bacterial overgrowth syndrome. Am J Gastroenterol 1999; 94:1327.
- Malik BA, Xie YY, Wine E, Huynh HQ. Diagnosis and pharmacological management of small intestinal bacterial overgrowth in children with intestinal failure. Can J Gastroenterol 2011; 25:41.
- Scarpellini E, Giorgio V, Gabrielli M, et al. Rifaximin treatment for small intestinal bacterial overgrowth in children with irritable bowel syndrome. Eur Rev Med Pharmacol Sci 2013; 17:1314.
- Pimentel M, Chang C, Chua KS, et al. Antibiotic treatment of constipation-predominant irritable bowel syndrome. Dig Dis Sci 2014; 59:1278.
- Vanderhoof JA, Young RJ, Murray N, Kaufman SS. Treatment strategies for small bowel bacterial overgrowth in short bowel syndrome. J Pediatr Gastroenterol Nutr 1998; 27:155.
- Lauritano EC, Gabrielli M, Scarpellini E, et al. Small intestinal bacterial overgrowth recurrence after antibiotic therapy. Am J Gastroenterol 2008; 103:2031.
- Lembo A, Pimentel M, Rao SS, et al. Repeat Treatment With Rifaximin Is Safe and Effective in Patients With Diarrhea-Predominant Irritable Bowel Syndrome. Gastroenterology 2016; 151:1113.
- Pimentel M, Constantino T, Kong Y, et al. A 14-day elemental diet is highly effective in normalizing the lactulose breath test. Dig Dis Sci 2004; 49:73.
- Stotzer PO, Blomberg L, Conway PL, et al. Probiotic treatment of small intestinal bacterial overgrowth by Lactobacillus fermentum KLD. Scand J Infect Dis 1996; 28:615.
- Hegar B, Hutapea EI, Advani N, Vandenplas Y. A double-blind placebo-controlled randomized trial on probiotics in small bowel bacterial overgrowth in children treated with omeprazole. J Pediatr (Rio J) 2013; 89:381.
- Gaon D, Garmendia C, Murrielo NO, et al. Effect of Lactobacillus strains (L. casei and L. Acidophillus Strains cerela) on bacterial overgrowth-related chronic diarrhea. Medicina (B Aires) 2002; 62:159.
- Zhong C, Qu C, Wang B, et al. Probiotics for Preventing and Treating Small Intestinal Bacterial Overgrowth: A Meta-Analysis and Systematic Review of Current Evidence. J Clin Gastroenterol 2017; 51:300.
- Gottlieb K, Wacher V, Sliman J, Pimentel M. Review article: inhibition of methanogenic archaea by statins as a targeted management strategy for constipation and related disorders. Aliment Pharmacol Ther 2016; 43:197.
- INITIAL APPROACH
- Antibiotic therapy
- Correction of micronutrient deficiency
- Treatment of associated ileocolitis
- TREATMENT RESPONSE AND RECURRENCE
- INADEQUATE RESPONSE TO INITIAL THERAPY OR RECURRENCE
- Subsequent antibiotic regimen
- Elemental diet
- PREVENTION OF RECURRENCE
- Treat the underlying etiology in all patients
- Antibiotic prophylaxis in selected patients
- Interventions with unclear role
- SUMMARY AND RECOMMENDATIONS