1. K59 Other functional intestinal disorders


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


    • functional disorders of stomach (K31.-)
    1. K59.0 Constipation

      1. K59.00 Constipation, unspecified

      2. K59.01 Slow transit constipation

      3. K59.02 Outlet dysfunction constipation

      4. K59.03 Drug induced constipation

      5. K59.04 Chronic idiopathic constipation

        Inclusion term(s):

        • Functional constipation
      6. K59.09 Other constipation

        Inclusion term(s):

        • Chronic constipation
    2. K59.1 Functional diarrhea

    3. K59.2 Neurogenic bowel, not elsewhere classified

    4. K59.3 Megacolon, not elsewhere classified

      Inclusion term(s):

      • Dilatation of colon
      1. K59.31 Toxic megacolon

      2. K59.39 Other megacolon

        Inclusion term(s):

        • Megacolon NOS
    5. K59.4 Anal spasm

      Inclusion term(s):

      • Proctalgia fugax
    6. K59.8 Other specified functional intestinal disorders

      1. K59.81 Ogilvie syndrome

        Inclusion term(s):

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

        Inclusion term(s):

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

Abbreviations used here:

NEC Not elsewhere classifiable
This abbreviation in the Tabular List represents “other specified”. When a specific code is not available for a condition, the Tabular List includes an NEC entry under a code to identify the code as the “other specified” code.

NOS Not otherwise specified
This abbreviation is the equivalent of unspecified.