ICD-10 Code H49.0 – Third [oculomotor] nerve palsy (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code H49.0 – Third [oculomotor] nerve palsy
What it is
H49.0 identifies paralysis or weakness of the third cranial nerve, which controls most eye movements, eyelid elevation, and pupil constriction. Use it when documentation specifically states oculomotor nerve palsy.
Clinical signs
Common findings include ptosis, outward and downward eye deviation, and double vision. Pupil involvement may occur; clinical features vary, so refer to documentation.
When to use this code
Use H49.0 when the provider documents third nerve palsy, oculomotor palsy, or equivalent wording. It may apply to unilateral or unspecified side when laterality is not documented. Code the condition itself, not the underlying cause, unless the record directs otherwise.
Do not use for
Do not use this code for other cranial nerve palsies, nonspecific diplopia, or general eye movement disorders. Check documentation if the note describes a different neurologic cause.
Coding tip
Verify laterality and any documented cause before coding, and use the most specific code supported by the record.