H42 Glaucoma in diseases classified elsewhere

Billable ICD-10-CM code, FY2026.

Excludes1 (never code together)

• glaucoma (in) onchocerciasis (B73.02)
• glaucoma (in) syphilis (A52.71)
• glaucoma (in) tuberculous (A18.59)
• neovascular secondary angle closure glaucoma (H40.84-)

Code first

• underlying condition, such as:
• amyloidosis (E85.-)
• aniridia (Q13.1)
• glaucoma (in) diabetes mellitus (E08.39, E09.39, E10.39, E11.39, E13.39)
• Lowe's syndrome (E72.03)
• Rieger anomaly (Q13.81)
• specified metabolic disorder (E70-E88)

Applies from H42 Glaucoma in diseases classified elsewhere

Excludes1 (never code together)

• glaucoma (in) onchocerciasis (B73.02)
• glaucoma (in) syphilis (A52.71)
• glaucoma (in) tuberculous (A18.59)
• neovascular secondary angle closure glaucoma (H40.84-)

Code first

• underlying condition, such as:
• amyloidosis (E85.-)
• aniridia (Q13.1)
• glaucoma (in) diabetes mellitus (E08.39, E09.39, E10.39, E11.39, E13.39)
• Lowe's syndrome (E72.03)
• Rieger anomaly (Q13.81)
• specified metabolic disorder (E70-E88)

Risk adjustment (HCC)

• RxHCC V08: HCC 244 — Other Non-Acute Glaucoma

MS-DRG index

Defines the logic of DRG(s) 124-125 in MDC 02.

Approximate ICD-9-CM (GEMs)

• 365.44 Glaucoma associated with systemic syndromes (approximate)

Medicare Code Edits (MCE v43.1 (April 2026))

• Manifestation codes as principal diagnosis: Manifestation codes describe the manifestation of an underlying disease, not the disease itself, and are not allowed as principal diagnosis.

Code annotations containing back-references to H42

Back-references to H42

• Use Additional: E08.39 Diabetes mellitus due to underlying condition with other diabetic ophthalmic complication ("diabetic glaucoma (H40-H42)")
• Use Additional: E09.39 Drug or chemical induced diabetes mellitus with other diabetic ophthalmic complication ("diabetic glaucoma (H40-H42)")
• Use Additional: E10.39 Type 1 diabetes mellitus with other diabetic ophthalmic complication ("diabetic glaucoma (H40-H42)")
• Use Additional: E11.39 Type 2 diabetes mellitus with other diabetic ophthalmic complication ("diabetic glaucoma (H40-H42)")
• Use Additional: E13.39 Other specified diabetes mellitus with other diabetic ophthalmic complication ("diabetic glaucoma (H40-H42)")
• Use Additional: E72.03 Lowe's syndrome ("code for associated glaucoma (H42)")
• Code First: H26.23 Glaucomatous flecks (subcapsular) ("underlying glaucoma (H40-H42)")
• Use Additional: Q13.1 Absence of iris ("code for associated glaucoma (H42)")
• Use Additional: Q13.81 Rieger anomaly ("code for associated glaucoma (H42)")

Back-references to H42

• Use Additional: E08.39 Diabetes mellitus due to underlying condition with other diabetic ophthalmic complication ("diabetic glaucoma (H40-H42)")
• Use Additional: E09.39 Drug or chemical induced diabetes mellitus with other diabetic ophthalmic complication ("diabetic glaucoma (H40-H42)")
• Use Additional: E10.39 Type 1 diabetes mellitus with other diabetic ophthalmic complication ("diabetic glaucoma (H40-H42)")
• Use Additional: E11.39 Type 2 diabetes mellitus with other diabetic ophthalmic complication ("diabetic glaucoma (H40-H42)")
• Use Additional: E13.39 Other specified diabetes mellitus with other diabetic ophthalmic complication ("diabetic glaucoma (H40-H42)")
• Use Additional: E72.03 Lowe's syndrome ("code for associated glaucoma (H42)")
• Code First: H26.23 Glaucomatous flecks (subcapsular) ("underlying glaucoma (H40-H42)")
• Use Additional: Q13.1 Absence of iris ("code for associated glaucoma (H42)")
• Use Additional: Q13.81 Rieger anomaly ("code for associated glaucoma (H42)")

Diagnosis Index entries for H42

• Glaucoma › in (due to) › amyloidosis
• Glaucoma › in (due to) › aniridia
• Glaucoma › in (due to) › endocrine disease NOS
• Glaucoma › in (due to) › Lowe's syndrome
• Glaucoma › in (due to) › metabolic disease NOS
• Glaucoma › in (due to) › Rieger anomaly

Nearby codes

• H42 Glaucoma in diseases classified elsewhere (this code)