2026 ICD-10-CM Diagnosis Code K59.89Other specified functional intestinal disorders

ICD-10-CM CodesK00–K95K55-K64K59

ICD-10-CM K59.89
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

K59.89 is a billable ICD-10-CM diagnosis code for other specified functional intestinal disorders. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 391 through 392. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Other specified and unspecified gastrointestinal disorders.

Code Identity

ICD-10-CM Code
K59.89
Billable Status
Yes — Valid for Submission
Code Describes
Other specified functional intestinal disorders
Short Description
Other specified functional intestinal disorders
Same as the full description in the CMS dataset.
Parent Code
Other specified functional intestinal disorders

Code Classification

ChapterK00–K95Diseases of the digestive system
SectionK55-K64Other diseases of intestines
CategoryK59Other functional intestinal disorders
This CodeK59.89Other specified functional intestinal disorders

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Abnormal large bowel motility
  • Abnormal small intestine secretion
  • Absence of peristalsis of intestine
  • Acute intestinal pseudo-obstruction
  • Acute pseudo-obstruction of small intestine
  • Anal sphincter tone - finding
  • Appearance of anal orifice - finding
  • Atony of colon
  • Chronic atrial and intestinal dysrhythmia
  • Chronic idiopathic intestinal pseudo-obstruction
  • Chronic intestinal pseudo-obstruction
  • Chronic pseudo-obstruction of colon
  • Chronic pseudo-obstruction of small intestine
  • Dilatation of cecum
  • Dilatation of intestine
  • Dysmotility of small intestine caused by drug
  • Dysmotility of small intestine due to systemic disease
  • Finding of appearance of anus
  • Hepatic flexure syndrome
  • Hollow visceral neuropathy
  • Hyperactive rectosigmoid junction
  • Impaired intestinal epithelial cell digestion
  • Impaired intestinal epithelial cell transport
  • Impaired intestinal epithelial cell transport of amino acids
  • Impaired intestinal epithelial cell transport of carbohydrates
  • Impaired intestinal epithelial cell transport of fats
  • Impaired intestinal lymphatic transport of nutrients
  • Intestinal hurry
  • Irregularly dilated anal orifice
  • Megaduodenum
  • Motility disorder of intestine
  • Motility disorder of large intestine
  • Motility disorder of small intestine
  • Neuronal intestinal pseudo-obstruction
  • Payr's syndrome
  • Primary chronic pseudo-obstruction of gastrointestinal tract
  • Primary chronic pseudo-obstruction of large intestine
  • Primary chronic pseudo-obstruction of small intestine
  • Primary desmosis coli
  • Pseudodiarrhea
  • Pseudo-obstruction of gastrointestinal tract
  • Pseudo-obstruction of intestine
  • Reflex dilation of anus
  • Secondary intestinal pseudo-obstruction
  • Sick sinus syndrome
  • Small intestinal stasis syndrome
  • Toxic dilatation of intestine

Tabular List NotesGuidance

Coding notes and annotation back-references applicable to this code.

Inclusion Terms

  • Atony of colon
  • Pseudo-obstruction (acute) (chronic) of intestine

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

External Cause of Injuries IndexGuidance

References for this code in the External Cause of Injuries Index.

    • Achalasia(cardia) (esophagus)
      • sphincteral NEC
    • Atonia, atony, atonic
      • cecum
    • Atonia, atony, atonic
      • intestine
    • Contraction(s), contracture, contracted
      • anus
    • Contraction(s), contracture, contracted
      • rectum, rectal (sphincter)
    • Dilatation
      • anus
    • Dilatation
      • duodenum
    • Dilatation
      • ileum
    • Dilatation
      • jejunum
    • Disease, diseased
      • intestine
        • functional
          • specified NEC
    • Dyskinesia
      • intestinal
    • Dyspepsia
      • intestinal
    • Hyperemia(acute) (passive)
      • enteric
    • Hyperemia(acute) (passive)
      • intestine
    • Hypofunction
      • intestinal
    • Hypomotility
      • intestine
    • Ileus(bowel) (colon) (inhibitory) (intestine)
      • myxedema
    • Immobile, immobility
      • intestine
    • Irritable, irritability
      • duodenum
    • Irritable, irritability
      • ileum
    • Irritable, irritability
      • jejunum
    • Irritable, irritability
      • rectum
    • Paralysis, paralytic(complete) (incomplete)
      • digestive organs NEC
    • Pseudo-obstruction intestine(acute) (chronic) (idiopathic) (intermittent secondary) (primary)
    • Spasm(s), spastic, spasticity
      • duodenum
    • Stasis
      • cecum
    • Stasis
      • colon
    • Stasis
      • ileocecal coil
    • Stasis
      • ileum
    • Stasis
      • intestinal
    • Stasis
      • jejunum
    • Stasis
      • rectal
    • Syndrome
      • hepatic flexure
    • Syndrome
      • König's
    • Syndrome
      • splenic
        • flexure

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR DIG025
Other specified and unspecified gastrointestinal disorders
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Sick Sinus Syndrome

    a condition caused by dysfunctions related to the sinoatrial node including impulse generation (cardiac sinus arrest) and impulse conduction (sinoatrial exit block). it is characterized by persistent bradycardia, chronic atrial fibrillation, and failure to resume sinus rhythm following cardioversion. this syndrome can be congenital or acquired, particularly after surgical correction for heart defects.

Patient EducationClinical

Digestive Diseases

When you eat, your body breaks food down to a form it can use to build and nourish cells and provide energy. This process is called digestion.

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Code History & ChangesHistory

Replacement K59.89 replaces the following previously assigned code(s):

  • K59.8 - Other specified functional intestinal disorders
FY 2021AddedAdded to the ICD-10-CM code setEffective October 1, 2020.
FY 2022–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About K59.89Overview

Is K59.89 (Other specified functional intestinal disorders) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report other specified functional intestinal disorders on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does K59.89 group to?

When other specified functional intestinal disorders is the principal diagnosis on an inpatient stay, it groups to MS-DRG 391, 392, with relative weights from 0.7796 to 1.2683 depending on complications. Higher weights mean higher Medicare reimbursement.

Footnotes

[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.