ICDcodes.org
FY2027

H40 vs H42

H40 and H42 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 H42
neovascular secondary angle closure glaucoma (H40.84-)
H40

Glaucoma

Not billable
Chapter 7
Diseases of the eye and adnexa
Section
H40-H42
H42

Glaucoma in diseases classified elsewhere

Billable
Chapter 7
Diseases of the eye and adnexa
Section
H40-H42
Indexed under
  • Glaucoma › in › amyloidosis
  • Glaucoma › in › aniridia
  • Glaucoma › in › endocrine disease NOS
  • Glaucoma › in › Lowe's syndrome
  • Glaucoma › in › metabolic disease NOS

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