ICDcodes.org
FY2027

J41 vs J42

J41 and J42 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 J42
simple and mucopurulent chronic bronchitis (J41.-)
J41

Simple and mucopurulent chronic bronchitis

Not billable
Chapter 10
Diseases of the respiratory system
Section
J40-J4B
J42

Unspecified chronic bronchitis

BillableUnspecified
Chapter 10
Diseases of the respiratory system
Section
J40-J4B
Use when the record says
  • Chronic bronchitis NOS
  • Chronic tracheitis
  • Chronic tracheobronchitis
Indexed under
  • Pharyngotracheitis, chronic
  • Bronchitis › chronic (diffuse) (fibrinous) (hypostatic) (infective) (membranous)
  • Bronchitis › senile (diffuse) (fibrinous) (hypostatic) (infective) (membranous)
  • Bronchorrhea › chronic
  • Infection, infected, infective › trachea, chronic (opportunistic)

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