Recommendations

Document Overview

Design and created by Guideline Central in participation with the American College of Gastroenterology.

Small Intestinal Bacterial Overgrowth

American College of Gastroenterology

Publication Date: Feb 1, 2020

Page Last Updated: Jan 28, 2026

NKF/KDIGO Grading Table

Grade	Strength of Recommendation
Strong “We recommend”	For the Patient	For the Clinician	Policy
Strong “We recommend”	Most individuals in this situation would want the recommended course of action and only a small proportion would not.	Most individuals in this situation would want the recommended course of action and only a small proportion would not. The majority of individuals in this situation would want the suggested course of action, but many would not.	The recommendation can be adopted as policy in most situations.
Conditional (weak) “We suggest”	The majority of individuals in this situation would want the suggested course of action, but many would not.	Different choices will be appropriate for different patients. Decision aids may well be useful in helping individuals making decisions consistent with their values and preferences. Clinicians should expect to spend more time with patients when working toward a decision.	The recommendation is likely to require substantial debate and involvement of stakeholders before policy can be determined.
Expert Opinion		“KDOQI considers it reasonable”

Grade	Quality of Evidence
High	We are very confident that the true effect lies close to that of the estimate of the effect.
Moderate	We are moderately confident in the effect estimate. The true effect is likely to be close to the estimate of the effect, but there is a possibility that it is substantially different.
Low	Our confidence in the effect estimate is limited. The true effect may be substantially different from the estimate of the effect.
Very low	We have very little confidence in the effect estimate. The true effect is likely to be substantially different from the estimate of effect.
Insufficient	The quality of the evidence was insufficient to make a suggestion or recommendation (to support or not to support the intervention or topic) but important enough to acknowledge as an area for future study.

Document Overview

Document Title: Small Intestinal Bacterial Overgrowth

Authoring Society: American College of Gastroenterology

Document Publication Date: Feb 1, 2020

Page Last Reviewed/Updated: Jan 28, 2026

Document Type: Guideline

Country of Publication: United States

Full Text Freely Available: Yes

Full Text Guideline: journals.lww.com/ajg/Fulltext/2020/02000/ACG_Clinical_Guideline__Small_Intestinal_Bacterial.9.aspx?context=FeaturedArticles&collectionId=5

Source Citation: Pimentel, Mark MD, FRCP(C), FACG; Saad, Richard J. MD, FACG; Long, Millie D. MD, MPH, FACG (GRADE Methodologist); Rao, Satish S. C. MD, PhD, FRCP, FACG. ACG Clinical Guideline, The American Journal of Gastroenterology: February 2020 - Volume 115 - Issue 2 - p 165-178 doi: 10.14309/ajg.0000000000000501

Supplemental Implementation Resources

Document Scope, Criteria, and Use Cases

Document Objectives: This guideline statement evaluates criteria for diagnosis, defines the optimal methods for diagnostic testing, and summarizes treatment options for small intestinal bacterial overgrowth

Scope: Assessment and Screening, Diagnosis, Management, Treatment

Diseases/Conditions (MeSH)

D001424 - Bacterial Infections

D054328 - Proton Pump Inhibitors

D001419 - Bacteria

Keywords: bacterial overgrowth, culture, intestinal bacteria, proton pump inhibitor

Target Patient Population: Patients with small intestinal bacterial overgrowth

Inclusion Criteria: Male, Female, Adolescent, Adult, Older Adult

Health Care Settings: Ambulatory, Hospital, Outpatient

Intended Users: Nurse, Nurse Practitioner, Physician, Physician Assistant

Recommendation Development Processes & Methodology

Number of Source Documents: 115

Includes peer/external review process?: Yes

Includes public comment process?: No

Methodologist involvement?: Yes

Patient involvement?: No

Includes multi-disciplinary group?: Yes

Includes systematic review?: Yes

Grades quality of strength of evidence?: Yes

Grades quality of strength of recommendation?: Yes

Discloses funding source?: No

Discloses conflicts of interest?: Yes

Includes benefits/harms analysis with recommendations?: Yes

Small Intestinal Bacterial Overgrowth

Recommendations

Diagnosis of SIBO

Other conditions associated with SIBO

NKF/KDIGO Grading Table

Document Overview

Supplemental Implementation Resources

Document Scope, Criteria, and Use Cases

Recommendation Development Processes & Methodology