DxCodebookFY2027 · Oct 1, 2026 – Sep 30, 2027

Category · FY2027

K59 Other functional intestinal disorders

  • Header · not billable

K59 is not billable. The category heads 14 billable codes in FY2027, grouped under 7 subdivisions.

Index → code

Where it sits

  1. Chapter 11 Diseases of the digestive system (K00-K95)
  2. K55-K64 Other diseases of intestines (K55-K64)
  3. K59 Other functional intestinal disorders
Billable codes
14
Subdivisions
7
CC / MCC codes
3 / 0
HCC V28 codes
1
New FY2027
0
Index entries
76

Codes in K59

  1. K59.0
    Constipation
    Header
    Excludes1 1, Excludes2 1

    Excludes1

    • fecal impaction (K56.41) K56.41

    Excludes2

    • incomplete defecation (R15.0) R15.0
  2. K59.00
    Constipation, unspecified
    Billable
  3. K59.01
    Slow transit constipation
    Billable
  4. K59.02
    Outlet dysfunction constipation
    Billable
  5. K59.03
    Drug induced constipation
    Billable
    Use additional code 1

    Use additional code

    • code for adverse effect, if applicable, to identify drug (T36-T50 with fifth or sixth character 5) T36 T50
  6. K59.04
    Chronic idiopathic constipation
    Billable
    Inclusion terms 1

    Inclusion terms

    • Functional constipation
  7. K59.09
    Other constipation
    Billable
    Inclusion terms 1

    Inclusion terms

    • Chronic constipation
  8. K59.1
    Functional diarrhea
    Billable
    Excludes1 2

    Excludes1

    • diarrhea NOS (R19.7) R19.7
    • irritable bowel syndrome with diarrhea (K58.0) K58.0
  9. K59.2
    Neurogenic bowel, not elsewhere classified
    BillableCC
  10. K59.3
    Megacolon, not elsewhere classified
    Header
    Inclusion terms 1, Excludes1 4, Code first 1

    Inclusion terms

    • Dilatation of colon

    Excludes1

    • congenital megacolon (aganglionic) (Q43.1) Q43.1
    • megacolon (due to) (in) Chagas' disease (B57.32) B57.32
    • megacolon (due to) (in) Clostridium difficile (A04.7-) A04.7
    • megacolon (due to) (in) Hirschsprung's disease (Q43.1) Q43.1

    Code first

    • , if applicable (T51-T65) to identify toxic agent T51 T65
  11. K59.31
    Toxic megacolon
    BillableCC78
  12. K59.39
    Other megacolon
    BillableCC
    Inclusion terms 1

    Inclusion terms

    • Megacolon NOS
  13. K59.4
    Anal spasm
    Billable
    Inclusion terms 1

    Inclusion terms

    • Proctalgia fugax
  14. K59.8
    Other specified functional intestinal disorders
    Header
  15. K59.81
    Ogilvie syndrome
    Billable
    Inclusion terms 1

    Inclusion terms

    • Acute colonic pseudo-obstruction (ACPO)
  16. K59.89
    Other specified functional intestinal disorders
    Billable
    Inclusion terms 2

    Inclusion terms

    • Atony of colon
    • Pseudo-obstruction (acute) (chronic) of intestine
  17. K59.9
    Functional intestinal disorder, unspecified
    Billable

CC/MCC: as a secondary diagnosis, unless the principal diagnosis is on the code’s PDX exclusion list (MS-DRG v44 Appendix C; list on the code card).

Sources of each column.

Instructions

At K59

Excludes1

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

Excludes2

  • functional disorders of stomach (K31.-) K31

Notes that also apply

Chapter 11 instructions (Excludes2 8): printed on the chapter 11 page.

Index entries

  • Constipation (atonic) (neurogenic) (simple) (spastic) → K59.00
  • Dyschezia → K59.00
  • Macrosigmoid → K59.39
  • Megacolon (acquired) (functional) (not Hirschsprung's disease) (in) → K59.39
  • Megasigmoid → K59.39
  • Proctospasm → K59.4
  • ACPO (acute colonic pseudo-obstruction) → K59.81
  • Pseudo-obstruction intestine (acute) (chronic) (idiopathic) (intermittent secondary) (primary) → K59.89
  • Constipation (atonic) (neurogenic) (simple) (spastic)slow transit → K59.01
  • Constipation (atonic) (neurogenic) (simple) (spastic)outlet dysfunction → K59.02
  • Constipation (atonic) (neurogenic) (simple) (spastic)drug-induced → K59.03
  • Constipation (atonic) (neurogenic) (simple) (spastic)functional → K59.04
  • Constipation (atonic) (neurogenic) (simple) (spastic)chronic → K59.09
  • Constipation (atonic) (neurogenic) (simple) (spastic)specified NEC → K59.09
  • Diarrhea, diarrheal (disease) (infantile) (inflammatory)functional → K59.1
  • Diarrhea, diarrheal (disease) (infantile) (inflammatory)neurogenic → K59.1
  • Neurogenicbowel NEC → K59.2
  • Megacolon (acquired) (functional) (not Hirschsprung's disease) (in)toxic NEC → K59.31
  • Dilatationcolon → K59.39
  • Dilatationrectum → K59.39
  • Syndromefaulty bowel habit → K59.39
  • Proctalgiafugax → K59.4
  • Proctalgiaspasmodic → K59.4
  • Spasm(s), spastic, spasticityanus, ani (sphincter) (reflex) → K59.4
  • Spasm(s), spastic, spasticityrectum (sphincter) → K59.4
  • Pseudo-obstruction intestine (acute) (chronic) (idiopathic) (intermittent secondary) (primary)colonic → K59.81
  • SyndromeOgilvie → K59.81
  • Achalasia (cardia) (esophagus)sphincteral NEC → K59.89
  • Atonia, atony, atoniccecum → K59.89
  • Atonia, atony, atonicintestine → K59.89
  • Contraction(s), contracture, contractedanus → K59.89
  • Contraction(s), contracture, contractedrectum, rectal (sphincter) → K59.89
  • Dilatationanus → K59.89
  • Dilatationduodenum → K59.89
  • Dilatationileum → K59.89
  • Dilatationjejunum → K59.89
  • Dyskinesiaintestinal → K59.89
  • Dyspepsiaintestinal → K59.89
  • Hyperemia (acute) (passive)enteric → K59.89
  • Hyperemia (acute) (passive)intestine → K59.89

36 more, longer entries are not listed; the search box finds them by word.

NCHS Alphabetic Index. Index first, then the Tabular List.

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