ICD10

ICD-10 Code H40: Glaucoma

H40 is an ICD-10 diagnosis entry used to group records related to Glaucoma. You may see this entry in coding references, medical records, or claims workflows when a broader diagnosis category is being reviewed before a more specific code is chosen. ICD-10 entries help standardize how diagnoses are organized for coding, reporting, analytics, and documentation. This code sits within the broader ICD-10 area for Diseases of the eye and adnexa (H00-H59).

Reviewed by HealthAssure Clinical TeamUpdated 21 May 2026

What is this code?

ICD-10 entries help standardize how diagnoses are organized for coding, reporting, analytics, and documentation. This code sits within the broader ICD-10 area for Diseases of the eye and adnexa (H00-H59).

When is it used?

  • May be used when a clinician documents glaucoma in a patient's medical record.
  • May appear in hospital records, claims, referrals, and clinical documentation.
  • This code may act more like a grouping or parent code, so a more specific child code may be used in final documentation when available.

What it does not mean

  • A code alone does not explain severity, treatment plan, or outcome.
  • A medical code should not be treated as a substitute for a doctor's diagnosis or advice.
  • This entry may represent a broader category rather than the most specific billable code.

Code hierarchy

chapter
7Diseases of the eye and adnexa (H00-H59)
block
H40-H42Glaucoma
currentH40-H42

Official coding notes

Excludes1 (do not code together)
  • absolute glaucoma (H44.51-)
  • congenital glaucoma (Q15.0)
  • traumatic glaucoma due to birth injury (P15.3)

Where you may see this code

You may see this entry in coding references, medical records, or claims workflows when a broader diagnosis category is being reviewed before a more specific code is chosen.

Related specialists

Ophthalmologist

Coding guidelines

Compatibility

Legacy code aligns to an official FY 2026 category. Frontend should resolve to the official category page and surface the billable child codes.
Legacy codes
H40
Replacement codes
H40.9 — Unspecified glaucoma

Common synonyms

Glaucoma

Frequently asked questions

Code details

CodeH40
SystemICD10
Display nameGlaucoma
ChapterDiseases of the eye and adnexa (H00-H59)
BlockGlaucoma

Flags

BillableNo
Valid clinical useNo

Source

SourceICD-10
Version2026-annual
Releaseannual
Year2026

About this content

This page is prepared by HealthAssure's clinical team using official coding standards from ICD-10. AI tools assist with drafting explanations, which are then reviewed and verified by healthcare professionals for accuracy. This content is for informational purposes and does not replace professional medical advice. Meet our team.

ICD-10 Code H40 for Glaucoma | HealthAssure