ICD-10 Code H40.42 – Glaucoma secondary to eye inflammation, left eye (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code H40.42 – Glaucoma secondary to eye inflammation, left eye
What it is
This code identifies glaucoma caused by inflammation in the left eye. Use it when the record shows uveitis-related or other inflammatory glaucoma affecting that eye.
Clinical signs
Typical findings include elevated intraocular pressure with signs of ocular inflammation, such as redness, pain, photophobia, or blurred vision. Clinical features vary; refer to documentation.
When to use this code
Use H40.42 when the provider documents glaucoma secondary to eye inflammation in the left eye. It is appropriate when the inflammatory cause and laterality are both clearly stated. If the note does not specify the eye or the cause, check documentation before coding.
Do not use for
Do not use this code for primary glaucoma or for glaucoma due to another secondary cause, such as trauma or medication, unless the record supports it. Do not assume laterality if the left eye is not documented.
Coding tip
Confirm both the inflammatory etiology and left-eye laterality in the provider note before assigning H40.42.