Excludes1 pair

F45.8 vs K31.3

F45.8 and K31.3 are not coded together. ICD-10-CM declares them mutually exclusive with an Excludes1 note — the two conditions are not expected to occur together, so exactly one of them is normally correct for a given encounter. The Official Guidelines carve out one exception: if the two conditions are clearly unrelated to each other, both may be reported.

The official note, declared on K31.3
neurotic pylorospasm (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)
K31.3

Pylorospasm, not elsewhere classified

BillableUnspecified
Chapter 11
Diseases of the digestive system
Section
K20-K31
Indexed under
  • Pylorospasm NEC (reflex)
  • Spasm, spastic, spasticity › pylorus NEC
  • Obstruction, obstructed, obstructive › stomach NEC › due to pylorospasm

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