ICD-10 Code H10.9 – Unspecified conjunctivitis (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code H10.9 – Unspecified conjunctivitis
What it is
H10.9 identifies conjunctivitis when the provider documents inflammation of the conjunctiva but does not specify the cause, type, or laterality. Use it for a general conjunctivitis diagnosis without further detail.
Clinical signs
Typical findings include red, irritated eyes, tearing, and discharge or crusting. Clinical features vary; refer to documentation when the record does not clearly describe infectious, allergic, or other specified conjunctivitis.
When to use this code
Use this code when the chart states conjunctivitis and provides no additional detail that supports a more specific code. It also fits cases where the clinician documents “unspecified conjunctivitis” or the etiology is not established. If laterality or cause is documented, check whether a more specific code applies.
Do not use for
Do not use H10.9 when the record identifies allergic, chronic, mucopurulent, or other specified conjunctivitis. Also avoid it if the documentation supports a different eye disorder entirely.
Coding tip
Query the provider if the note mentions cause, type, or eye laterality that could support a more specific conjunctivitis code.