Antibiotics for SIBO: Understanding Limitations & Alternative Treatments

Small intestinal bacterial overgrowth, or SIBO, is a condition where bacteria is found in excess. It can lead to an array of symptoms, but the most common ones include bloating, excessive gas, stomach pain or discomfort, and diarrhea and/or constipation. To learn more about SIBO, check out this article IBS 101: What is SIBO over at Foodguides. 

Disrupting the Gut Microbiome: Unintended Consequences

The standard treatment for SIBO is antibiotic therapy. Typically, doctors will not start treatment for SIBO until SIBO is confirmed by testing, most commonly breath testing. Doctors will choose which antibiotic to prescribe after evaluating the pattern of bacterial overgrowth, recent or repeated exposure to antibiotics, antibiotic allergies, and cost. Since the discovery of antibiotics in the 20th century, they have been noted for increased life expectancy. Although antibiotics are great and have transformed medicine, they unfortunately come with some downfalls. One major downfall is the disruption of our gut microbiota. The gut microbiome is unique to everyone. It is responsible for many of the functions in our body and is key to our health and well-being. 

Antibiotics have been shown to decrease the diversity of our microbiota species and the different microorganisms living in our gut. This means that the balance of our good and bad bacteria may become off. Good bacteria may become less, and bad bacteria may become more abundant. Not only can the diversity of our microbiota change with antibiotics, but we can also see metabolic shifts. One study showed that low-dose antibiotics increased extra body fat and elevated hormones linked to breaking down carbohydrates, fats, and cholesterol. Another problem that can be paired with a decrease in the diversity of our microbiota species is antibiotic resistance, meaning antibiotics no longer work at treating a specific condition.

Recurrence of SIBO: The Challenge of Long-Term Management

Around 44% of people with SIBO have a recurrence of symptoms after completing antibiotic therapy. For these people who experience a recurrence of SIBO, it is important to identify that the correct type of antibiotic is being used. This is typically done by small bowel aspiration, a procedure that takes a fluid sample from your intestines. Besides ensuring the correct antibiotic is being used,  healthcare providers may look at any underlying conditions such as avoiding medications that may slow down food movement in your GI tract and improve blood sugar levels. 

Luckily, there may be alternatives for those who don’t want to try antibiotics upfront. A Low FODMAP diet, probiotics, prebiotics, herbal remedies, and stress management have been shown to be helpful. Prior to starting any natural remedies, please talk to your healthcare provider. It is key to know that some of these natural remedies may take more time than conventional treatments to show improvements. It is also essential to be in tune with your body and watch for symptoms that get worse or return. In these cases, it may warrant further evaluation and treatment.

1. _{Cho, I., Yamanishi, S., Cox, L., Methé, B. A., Zavadil, J., Li, K., Gao, Z., Mahana, D., Raju, K., Teitler, I., Li, H., Alekseyenko, A. V., & Blaser, M. J. (2012). Antibiotics in early life alter the murine colonic microbiome and adiposity. Nature, 488(7413), 621–626. https://doi.org/10.1038/nature11400} 

2. _{Patangia, D. V., Anthony Ryan, C., Dempsey, E., Paul Ross, R., & Stanton, C. (2022). Impact of antibiotics on the human microbiome and consequences for host health. MicrobiologyOpen, 11(1), e1260. https://doi.org/10.1002/mbo3.1260} 

3. _{Ramirez, J., Guarner, F., Bustos Fernandez, L., Maruy, A., Sdepanian, V. L., & Cohen, H. (2020). Antibiotics as Major Disruptors of Gut Microbiota. Frontiers in cellular and infection microbiology, 10, 572912. https://doi.org/10.3389/fcimb.2020.572912} 

4. _{Rao, S. S. C., & Bhagatwala, J. (2019). Small Intestinal Bacterial Overgrowth: Clinical Features and Therapeutic Management. Clinical and translational gastroenterology, 10(10), e00078. https://doi.org/10.14309/ctg.0000000000000078} 

5. _{Shah, A., & Holtmann, G. (2024, February 22). Small intestinal bacterial overgrowth: management. UpToDate. https://www.uptodate.com/contents/small-intestinal-bacterial-overgrowth-management}