ICD-10 Code G45.9 – Transient cerebral ischemic attack, unspecified (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code G45.9 – Transient cerebral ischemic attack, unspecified
What it is
G45.9 identifies a transient ischemic attack, or brief interruption of brain blood flow, when the specific type is not documented. It is used when the episode resolved and no more precise TIA subtype is recorded.
Clinical signs
Clinical features vary; refer to documentation. Typical notes describe sudden, temporary neurologic deficits such as weakness, speech difficulty, vision loss, or numbness that improve completely or nearly completely.
When to use this code
Use G45.9 when the provider documents TIA, transient cerebral ischemia, or similar wording without naming a more specific category. This code also fits when the record confirms a resolved ischemic episode but does not specify the affected artery or mechanism.
If the chart later clarifies the subtype, code to the documented specificity instead. Check documentation for whether the event is truly transient and whether another diagnosis better explains the symptoms.
Do not use for
Do not use this code for completed ischemic stroke, hemorrhagic stroke, or persistent neurologic deficits. Do not assign it when the note only says possible TIA or when documentation supports another definite cause.
Coding tip
Code G45.9 only after you confirm the episode was transient and the provider did not document a more specific TIA type.