Overgrowth - intestinal bacteria; Bacterial overgrowth - intestine; Small intestinal bacterial overgrowth; SIBO
Small bowel bacterial overgrowth is a condition in which very large numbers of bacteria grow in the small intestine.
Most of the time, unlike the large intestine, the small intestine does not have a large number of bacteria. Excess bacteria in the small intestine may use up the nutrients needed by the body. As a result, a person may become malnourished.
The breakdown of nutrients by the excess bacteria can also damage the lining of the small intestine. This can make it even harder for the body to absorb nutrients.
Conditions that can lead to overgrowth of bacteria in the small intestine include:
The most common symptoms are:
Other symptoms may include:
Your health care provider will perform a physical exam and ask about your medical history. Tests may include:
The goal is to treat the cause of the bacterial overgrowth. Treatment may include:
A lactose-free diet can be helpful.
Severe cases lead to malnutrition. Other possible complications include:
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Manolakis CS, Rutland TJ, Di Palma JA. Small intestinal bacterial overgrowth. In: McNally PR, ed. GI/Liver Secrets Plus. 5th ed. Philadelphia, PA: Elsevier Saunders; 2015:chap 44.
Sundaram M, Kim J. Short bowel syndrome. In: Yeo CJ, ed. Shackelford's Surgery of the Alimentary Tract. 8th ed. Philadelphia, PA: Elsevier; 2019:chap 79.BACK TO TOP
Review Date: 5/27/2020
Reviewed By: Jenifer K. Lehrer, MD, Department of Gastroenterology, Aria - Jefferson Health Torresdale, Jefferson Digestive Diseases Network, Philadelphia, PA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
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