ICD-10 Code H40.5 – Glaucoma secondary to other eye disorders (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code H40.5 – Glaucoma secondary to other eye disorders
What it is
H40.5 identifies glaucoma that develops because of another eye disorder. Use it when the record shows the glaucoma is secondary, not primary or unspecified.
Clinical signs
Clinical features vary; refer to documentation. Findings may include optic nerve damage, visual field loss, or elevated intraocular pressure when noted by the clinician.
When to use this code
Use H40.5 when the provider documents glaucoma caused by another ocular condition, such as inflammation, trauma, or a lens disorder. Code the underlying eye condition separately when instructed by the record and coding guidelines.
If the chart only says “glaucoma” without a secondary cause, check documentation before assigning this code. Verify that the relationship between the eye disorder and glaucoma is clearly stated.
Do not use for
Do not use this code for primary glaucoma or for glaucoma secondary to drugs, which has a different category. If the cause is not documented, check documentation.
Coding tip
Always capture the documented underlying eye disorder first, because H40.5 alone does not explain the cause.