Is H40.42X3 a billable ICD-10-CM code?

Yes. H40.42X3 is a billable, specific ICD-10-CM code and is valid for submission on a claim.

Where does H40.42X3 sit in the tabular list?

Diseases of the eye and adnexa (H00-H59), in the block Glaucoma (H40-H42).

What cannot be coded together with H40.42X3?

H40.42X3 carries Excludes1 notes, which means the conditions they list can never be coded together with it on the same encounter. Some are written on the categories above H40.42X3 (H40) and apply to it just the same.

H40.42X3

H40.42X3 — Glaucoma secondary to eye inflammation, left eye, severe stage

Billable / specific codeICD-10-CMleft

H40.42X3 is a billable, specific ICD-10-CM code for glaucoma secondary to eye inflammation, left eye, severe stage. It is valid for submission on a claim.

7th character "3" — severe stage

One of the following 7th characters is to be assigned to each code in subcategory H40.4 to designate the stage of glaucoma

0: stage unspecified
1: mild stage
2: moderate stage
3: severe stage
4: indeterminate stage

Excludes1 inherited from the categories above H40.42X3

These are not written on H40.42X3, but they bind it: a note on a category applies to every code beneath it. Billing H40.42X3 with anything listed here is a denial.

Written on H40 — Glaucoma

absolute glaucoma (H44.51-)
congenital glaucoma (Q15.0)
traumatic glaucoma due to birth injury (P15.3)

Risk adjustment

H40.42X3 does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.

Medicare coverage

H40.42X3 is named in 21 Medicare coverage policies — 21 listing it as supporting medical necessity. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.

A53060Billing and Coding: Ophthalmology: Extended Ophthalmoscopy and Fundus Photography
A55639Billing and Coding: Chemotherapy Agents for Non-Oncologic Conditions
A56457Billing and Coding: Corneal Pachymetry
A56537Billing and Coding: Scanning Computerized Ophthalmic Diagnostic Imaging (SCODI)

Code history

H40.42X3 has not changed since FY2024 — no addition, revision or deletion across the three most recent ICD-10-CM releases.

Related codes at this level

Codes that share H40.42. If H40.42X3 is not quite right, the correct code is usually one of these.

Questions about H40.42X3

Is H40.42X3 a billable ICD-10-CM code?: Yes. H40.42X3 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
Where does H40.42X3 sit in the tabular list?: Diseases of the eye and adnexa (H00-H59), in the block Glaucoma (H40-H42).
What cannot be coded together with H40.42X3?: H40.42X3 carries Excludes1 notes, which means the conditions they list can never be coded together with it on the same encounter. Some are written on the categories above H40.42X3 (H40) and apply to it just the same.