ICD-10 Code H10.509 – Unspecified blepharoconjunctivitis, unspecified eye (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code H10.509 – Unspecified blepharoconjunctivitis, unspecified eye
What it is
This code identifies inflammation affecting both the eyelid margin and the conjunctiva in one eye, when the eye is not specified. Use it when the record says blepharoconjunctivitis but does not name the side.
Clinical signs
Typical findings include red, irritated eyes with eyelid crusting, swelling, tearing, and discomfort. Clinical features vary; refer to documentation.
When to use this code
Use H10.509 when the provider documents blepharoconjunctivitis and does not specify right or left eye. It also fits cases where the note confirms eyelid and conjunctival inflammation but laterality is missing. If the record is unclear, check documentation before coding.
Do not use for
Do not use this code for conjunctivitis without eyelid involvement or for blepharitis alone. Do not assign it if the record specifies a different eye or a more specific diagnosis.
Coding tip
Verify laterality in the chart; unspecified eye codes should be used only when the provider does not document right or left.