ICD-10 Code H00.021 – Hordeolum internum right upper eyelid (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code H00.021 – Hordeolum internum right upper eyelid
What it is
This code identifies an internal stye in the right upper eyelid. It refers to infection or inflammation of a meibomian gland within that eyelid.
Clinical signs
Typical findings include localized eyelid swelling, tenderness, and a painful red lump on the inner eyelid. Clinical features vary; refer to documentation.
When to use this code
Use H00.021 when the provider documents a hordeolum internum specifically in the right upper eyelid. Code it when the note clearly identifies the eyelid side and that the lesion is internal. If the record only says “stye” or does not specify location, check documentation.
Do not use for
Do not use this code for a chalazion, external hordeolum, or an eyelid lesion on another side. If the documentation is unclear, check documentation.
Coding tip
Verify both laterality and that the lesion is internal before assigning H00.021.