F45.8 vs K52.9
F45.8 and K52.9 can never be reported together. ICD-10-CM declares them mutually exclusive with an Excludes1 note, meaning the two conditions cannot occur in the same patient — so exactly one of them is correct for any given encounter.
The official note, declared on K52.9
psychogenic diarrhea (F45.8)
F45.8
Other somatoform disorders
Billable
- Chapter 5
- Mental, Behavioral and Neurodevelopmental disorders
- Section
- F40-F48
Use when the record says
- Psychogenic dysmenorrhea
- Psychogenic dysphagia, including 'globus hystericus'
- Psychogenic pruritus
- Psychogenic torticollis
- Somatoform autonomic dysfunction
- Teeth grinding
Indexed under
- Aerophagy, aerophagia (psychogenic)
- Angioneurosis
- Da Costa's syndrome
- Effort syndrome (psychogenic)
- Globus (hystericus)
K52.9
Noninfective gastroenteritis and colitis, unspecified
BillableUnspecified
- Chapter 11
- Diseases of the digestive system
- Section
- K50-K52
Use when the record says
- Colitis NOS
- Enteritis NOS
- Gastroenteritis NOS
- Ileitis NOS
- Jejunitis NOS
- Sigmoiditis NOS
Indexed under
- Cecitis
- Colitis (acute) (catarrhal) (chronic) (noninfective) (hemorrhagic)
- Enteritis (acute) (diarrheal) (hemorrhagic) (noninfective)
- Enterocolitis
- Gastroenteritis (acute) (chronic) (noninfectious)
These two codes sit in different chapters of the Tabular List, which is usually the clearest signal that they describe different underlying processes rather than different degrees of the same one.
Excludes1 is not always absolute: where two conditions covered by the note are genuinely unrelated, CMS guidance permits reporting both. Document the reasoning rather than assuming it. More on Excludes1 vs Excludes2 · FY2027