H42 Glaucoma in diseases classified elsewhere

The ICD-10-CM code for Glaucoma in diseases classified elsewhere is H42 (FY2026). It is a billable, claim-ready diagnosis code.

Classification

Chapter

7: Diseases of the eye and adnexa (H00-H59)

Section

H40-H42: Glaucoma (H40-H42)

Category H42

1 code (1 billable)

FY2026 Status

Stable since FY2024

U.S. Hospital Utilization

• An estimated 7,150 U.S. inpatient stays in 2023 included H42 among the documented diagnoses.

Source: National Inpatient Sample (NIS), Healthcare Cost and Utilization Project (HCUP), Agency for Healthcare Research and Quality, 2016–2023. National survey-weighted estimates.

Official Coding Guidelines

Glaucoma (TOC entry)

a. Glaucoma .............................................................................................................................. 48

Assigning glaucoma codes (use as many H40 codes as needed)

Assign as many codes from category H40, Glaucoma, as needed to identify the type of glaucoma, the affected eye, and the glaucoma stage.

Source: CMS — ICD-10-CM Official Guidelines for Coding and Reporting, FY2026

References

• CMS — ICD-10-CM Official Code Set and Guidelines, FY2026
• CDC/NCHS — ICD-10-CM Files and Browser Tool
• AHRQ — HCUP National Inpatient Sample, Frequencies by Diagnosis Code (2016–2023)