2027 ICD-10-CM Diagnosis Code K59Other functional intestinal disorders

ICD-10-CM Codes›K00–K95›K55-K64›K59

ICD-10-CM K59
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

K59 is a non-billable ICD-10-CM category code for other functional intestinal disorders, so it cannot be submitted on claims. Use a more specific code from this category instead, such as K59.00, K59.01, K59.02, and K59.03.

Code Identity

ICD-10-CM Code
K59
Billable Status
No — Non-Billable Category
Code Describes
Other functional intestinal disorders
Short Description
Other functional intestinal disorders
Same as the full description in the CMS dataset.
Chapter
K55-K64
Other diseases of intestines

Code Classification

ChapterK00–K95Diseases of the digestive system
SectionK55-K64Other diseases of intestines
CategoryK59Other functional intestinal disorders
This CodeK59Other functional intestinal disorders

Specific Coding for Other functional intestinal disordersOverview

Non-specific codes like K59 require more characters. Use one of these billable codes instead:

  • K59.0 for Constipation

  • Use K59.00 for Constipation, unspecified

  • Use K59.01 for Slow transit constipation

  • Use K59.02 for Outlet dysfunction constipation

  • Use K59.03 for Drug induced constipation

  • Use K59.04 for Chronic idiopathic constipation

  • Use K59.09 for Other constipation

  • Use K59.1 for Functional diarrhea

  • Use K59.2 for Neurogenic bowel, not elsewhere classified

  • K59.3 for Megacolon, not elsewhere classified

  • Use K59.31 for Toxic megacolon

  • Use K59.39 for Other megacolon

  • Use K59.4 for Anal spasm

  • K59.8 for Other specified functional intestinal disorders

  • Use K59.81 for Ogilvie syndrome

  • Use K59.89 for Other specified functional intestinal disorders

  • Use K59.9 for Functional intestinal disorder, unspecified

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to K59: its own notes plus those printed at Chapter 11. A note printed at a category, block or chapter applies to every code under it.

Excludes1

Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.

  • change in bowel habit NOS (R19.4)
  • intestinal malabsorption (K90.-)
  • psychogenic intestinal disorders (F45.8)

Excludes2

Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.

On K59 itself
  • functional disorders of stomach (K31.-)
From Chapter 11 (K00-K95) Diseases of the digestive system applies to 863 codes
  • certain conditions originating in the perinatal period (P04-P96)
  • certain infectious and parasitic diseases (A00-B99)
  • complications of pregnancy, childbirth and the puerperium (O00-O9A)
  • congenital malformations, deformations and chromosomal abnormalities (Q00-Q99)
  • endocrine, nutritional and metabolic diseases (E00-E88)
  • injury, poisoning and certain other consequences of external causes (S00-T88)
  • neoplasms (C00-D49)
  • symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)

Source: CMS ICD-10-CM Tabular List. How to read instructional notes.

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 HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About K59Overview

What is the ICD-10 code for other functional intestinal disorders?

K59 is the ICD-10-CM category for other functional intestinal disorders, but it is a non-billable header: claims need a more specific code from this category, listed on this page.

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

No. This is a category header that groups the codes for other functional intestinal disorders, and headers cannot be submitted on claims. Claims for other functional intestinal disorders need a more specific code from this category, such as K59.00, K59.01, and K59.02.

Can K59 be reported with R19.4?

Not as a rule. The Excludes1 note on K59 lists "change in bowel habit NOS (R19.4)". An Excludes1 note means the excluded code is never reported together with this one; the only exception is when the two conditions are unrelated to each other (Official Guidelines, Section I.A.12.a).