ICD-10 Code K59.89 – Other specified functional intestinal disorders (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code K59.89 – Other specified functional intestinal disorders
What it is
K59.89 is used for functional intestinal disorders that do not fit a more specific ICD-10 category. It describes bowel dysfunction without a clearly defined structural cause.
Clinical signs
Clinical features vary; refer to documentation. You may see abdominal discomfort, altered bowel habits, bloating, or other nonspecific intestinal symptoms when no organic disorder is identified.
When to use this code
Use this code when the provider documents a functional intestinal disorder and no more specific code applies. It is appropriate for nonspecific or “other specified” bowel dysfunctions after evaluation rules out a defined condition. Check documentation for the exact diagnosis wording.
Do not use for
Do not use it for constipation, diarrhea, irritable bowel syndrome, or other separately coded intestinal disorders. If the record names a specific condition, code that diagnosis instead.
Coding tip
Code the provider’s exact wording and avoid K59.89 when a more specific intestinal disorder is documented.