K59 ICD-10-CM Code: Other functional intestinal disorders
Billing Status: NO. This is a clinician non-billable / parent hierarchy grouping in the ICD-10-CM system.
Coding at a Glance
- Tabular directives
- 3 Excludes1 · 1 Excludes2
Coding instructions
Official Tabular Instructional Notes: the inclusion, exclusion and sequencing notes published for K59 in the official ICD-10-CM tabular list, quoted as published.
Source: CMS/CDC — ICD-10-CM Tabular ListRelease: FY2026Effective: October 1, 2025
Excludes1 — Not Coded Here
Conditions generally not reported together with this code (Excludes1) -- an error unless the two conditions are documented as unrelated to each other (ICD-10-CM Official Guidelines, Section I.A.12.a).
- change in bowel habit NOS (R19.4) Compare K59 vs R19.4 →
- intestinal malabsorption (K90.-) Compare K59 vs K90 →
- psychogenic intestinal disorders (F45.8) Compare K59 vs F45.8 →
Excludes2 — Not Included Here
Conditions not covered by this code, but which may be reported alongside it when both are present.
- functional disorders of stomach (K31.-) Compare K59 vs K31 →
Coder workflow for K59
MedCoder structured workflow — derived from this code’s own official record
Before you code K59
- K59 is not reportable as written. Select the more specific code beneath it that the documentation supports. Codes are reported to the highest level of specificity the classification provides (Guidelines I.B.2).
ReviewK59.0, K59.1, K59.2, K59.3, K59.4, K59.8, K59.9
See the relationships section · Guide: How to choose an ICD-10-CM code →
- “Other” (NEC) means the condition is specified in the record but no dedicated code captures it. Confirm the documented form is not one a sibling code names before settling on K59; if the record states no specifics at all, the unspecified sibling applies instead. “Other” codes are for documented conditions the classification gives no specific code; “unspecified” codes are for records lacking the detail (Guidelines I.A.9.a, I.A.9.b).
See the relationships section · Guide: Other vs unspecified (NEC vs NOS) →
- Check the Excludes1 note: if the documentation supports a condition named there, do not simply proceed with K59. Excludes1 conditions are not reported together with this code unless the record shows they are unrelated (Guidelines I.A.12.a).
Choose the right path
- Does the documentation support one of the more specific codes beneath K59?
Yes → Select that code and continue the checks below on its own page.
No → K59 cannot be reported as written; query for the specificity its subcategory needs. - Does the documentation support a condition named in K59’s Excludes1 note?
Yes → Do not simply proceed: review the excluded code. Both are reported only when the record shows the two conditions are unrelated.
No → Continue.
Consider K59. Then confirm the code is valid for the date of service in the Verify section.
Documentation check
- The provider’s diagnostic statement
- Codes are assigned from the provider’s documented diagnosis, not from clinical criteria, test values or a medication list (Guidelines I.A.19).
- Any detail beyond this code’s title
- What the record states that a more specific sibling code would capture — or its absence, which itself supports the unspecified code.
Official instructions as workflow
Excludes1 — check before selecting K59(3 notes)
Coding workflow: If the documentation supports a condition named in this note, do not simply proceed with K59: the two are not reported together. The one exception is when the record shows the two conditions are unrelated to each other.
See the official tabular notes · Guidelines I.A.12.a
Excludes2 — not part of K59(1 note)
Coding workflow: The conditions named in this note are not included in K59. When the record documents both, both may be reported; the note is a boundary, not a prohibition.
CompareK31
See the official tabular notes · Guidelines I.A.12.b
Coding decision scenarios
Pattern scenarios for this code’s structure — decision rules, not clinical cases
Documentation: Both the condition K59 describes and a condition named in its Excludes1 note are documented for the same encounter.
Coding question: Can both codes be reported?
Path: Review the Excludes1 note and the excluded code, and look for a provider statement on whether the two conditions are related.
Reason: Excludes1 means the two are not coded together; the exception is when the record shows the conditions are unrelated to each other (Guidelines I.A.12.a).
Every row is derived from this code’s own record — its title, tabular notes, 7th-character family and same-category siblings — with fixed MedCoder wording; nothing is inferred about a patient. The official notes and guideline text are in the sections each row links to, and they control.
Code Overview
MedCoder summary Summary composed by MedCoder from this code's official ICD-10-CM record. The tabular instructional notes themselves appear verbatim below.
Verify Before Coding
From the code registry, the Medicare Code Editor, and the MS-DRG Definitions Manual. Check it against a full claim in Claim Check.
Contextual Map
Every relationship of K59 in one view: hierarchy, official tabular instructions in both directions, clinical classification, risk adjustment, MS-DRG participation, index terms and change history — each edge carrying the CMS source it derives from.
Run K59 with these 4 related codes in Claim Check
Hierarchy
- K00-K95 — Chapter 11: Diseases of the Digestive System (K00-K95) (K00-K95)[Hierarchy]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- K55-K64 — Other diseases of intestines[Hierarchy]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
Excludes1
- F45.8 — Other somatoform disorders[Excludes1]: “psychogenic intestinal disorders (F45.8)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
- K90 — Intestinal malabsorption[Excludes1]: “intestinal malabsorption (K90.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
- R19.4 — Change in bowel habit[Excludes1]: “change in bowel habit NOS (R19.4)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
Excludes2
- K31 — Other diseases of stomach and duodenum[Excludes2]: “functional disorders of stomach (K31.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
Nearest codes (17)
- K59.0 — Constipation[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- K59.00 — Constipation, unspecified[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- K59.01 — Slow transit constipation[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- K59.02 — Outlet dysfunction constipation[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- K59.03 — Drug induced constipation[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- K59.04 — Chronic idiopathic constipation[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- K59.09 — Other constipation[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- K59.1 — Functional diarrhea[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- and 9 more
Change history
- FY2016 — In the code set at ICD-10-CM adoption [Change history]— CMS release files (code change ledger) · icd10cm-fy2016
Common coding questions
Can K59 be billed directly?
No. K59 (Other functional intestinal disorders) is a non-billable ICD-10-CM category code. A more specific billable subcode must be selected based on clinical documentation.
Sources for this page
Codes, titles, notes, index terms and mappings on this page are transcribed from the datasets below. Relationships MedCoder computed and text MedCoder wrote are labelled where they appear.
- Code, title, tabular notes and index terms Official source data
- CMS/CDC ICD-10-CM FY2026 tabular list, index and tables, effective October 1, 2025 Release, file and checksum · Publisher’s page
- Claim edits Official source data
- CMS Definitions of Medicare Code Edits — v43.1 (April 2026) Release, file and checksum · Publisher’s page
- Change history and date-of-service validity Official source data
- CMS ICD-10-CM release addenda, ingested release by release into the change ledger Release, file and checksum · Publisher’s page
- Comparisons, relationships and the contextual map MedCoder structured relationship
- Computed by MedCoder from the tabular notes and tables above; every derived relationship is marked as derived where it appears
- Summary and FAQ answers MedCoder explanation
- Written by MedCoder to explain the sources above: drafted with AI assistance, checked by a person against the release files, and labelled as MedCoder text where it appears. Not official text.
Labels on this page: Official source data · MedCoder structured relationship · MedCoder explanation. How to read the labels · All data sources and release dates
Cite this page
Reference this page in a research guide, syllabus or article. The release is included because code content changes each year.
MedCoder.ai. "K59 — Other functional intestinal disorders." ICD-10-CM FY2026. https://medcoder.ai/icd10/code/k59-other-functional-intestinal-disorders
Change history
- FY2016 — October 1, 2015In the code set at ICD-10-CM adoptionOther functional intestinal disorders
No changes since FY2016 — additions, deletions, description changes and billable-status changes are tracked through FY2027 (effective October 1, 2026), and none are recorded for this code. Note changes are tracked from FY2027 only.
Nearest Codes in This Family
Official ICD-10-CM classifications closest to K59 in its code family, with their registry titles.
- K59.0 — Constipation
- K59.00 — Constipation, unspecified
- K59.01 — Slow transit constipation
- K59.02 — Outlet dysfunction constipation
- K59.03 — Drug induced constipation
- K59.04 — Chronic idiopathic constipation
- K59.09 — Other constipation
- K59.1 — Functional diarrhea
- K59.2 — Neurogenic bowel, not elsewhere classified
- K59.3 — Megacolon, not elsewhere classified
- K59.31 — Toxic megacolon
- K59.39 — Other megacolon
- K59.4 — Anal spasm
- K59.8 — Other specified functional intestinal disorders
- K59.81 — Ogilvie syndrome
- K59.89 — Other specified functional intestinal disorders
- K59.9 — Functional intestinal disorder, unspecified