ICD-10 Code K63.829 – Intestinal Methanogen Overgrowth, Unspecified (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code K63.829 – Intestinal methanogen overgrowth, unspecified
What it is
This code identifies intestinal methanogen overgrowth when the record does not specify a cause, site detail, or other qualifying information. It is used for documentation of excess methane-producing organisms in the intestine.
Clinical signs
Clinical features often include bloating, abdominal discomfort, and constipation, but presentation can vary. Use only when the chart supports intestinal methanogen overgrowth; if unclear, check documentation.
When to use this code
Use K63.829 when the clinician documents intestinal methanogen overgrowth without further specificity. It may also fit when the note confirms methane-predominant overgrowth but does not identify a more detailed diagnosis. If the record only mentions suspected overgrowth, code the documented suspicion carefully and follow facility policy.
Do not use for
Do not use this code for nonspecific bloating, constipation, or other gastrointestinal symptoms without documented intestinal methanogen overgrowth. Do not substitute it for other confirmed intestinal disorders; check documentation.
Coding tip
Assign this code only when the provider explicitly documents intestinal methanogen overgrowth, and verify whether the record includes additional specificity.