ICD-10 Code H66.42 – Suppurative otitis media, unspecified, left ear (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code H66.42 – Suppurative otitis media, unspecified, left ear
What it is
H66.42 identifies a suppurative middle ear infection in the left ear when the type is not further specified. Use it when documentation confirms pus-forming otitis media on the left side.
Clinical signs
Typical findings include ear pain, drainage if the tympanic membrane is perforated, and signs of middle ear inflammation. Clinical features vary; refer to documentation.
When to use this code
Use this code when the record clearly states suppurative otitis media and identifies the left ear, but does not name a more specific subtype. It also fits when the provider documents only “suppurative otitis media, left ear.” Check documentation if chronic, recurrent, or nonsuppurative features are mentioned.
Do not use for
Do not use H66.42 for otitis externa, nonsuppurative otitis media, or right or bilateral ear disease. If the note specifies a more detailed diagnosis, code that instead.
Coding tip
Confirm laterality and whether the provider documented suppurative disease, because missing detail can change the code selection.