G45.9 – Transient cerebral ischemic attack, unspecified

ICD-10-CM 2027 diagnosis code · Episodic and paroxysmal disorders

Billable code

ICD-10-CM code G45.9

Code: G45.9 (claims format: G459)
Description: Transient cerebral ischemic attack, unspecified
Billable: Yes – valid for HIPAA-covered transactions
Valid for: Dates of service October 1, 2026 – September 30, 2027 (FY2027)
Chapter: 6. Diseases of the nervous system (G00-G99)
Block: G40-G47 Episodic and paroxysmal disorders
Parent codes: G45

Notes for G45.9

Applicable to:

Spasm of cerebral artery
TIA
Transient cerebral ischemia NOS

Notes inherited from parent codes

Instructional notes at a category or block level apply to every code below it.

G45 – Transient cerebral ischemic attacks and related syndromes

Excludes1 (not coded here):

neonatal cerebral ischemia (P91.0)
transient retinal artery occlusion (H34.0-)

Index terms for G45.9

Entries in the ICD-10-CM alphabetic index that lead to this code:

Related codes in G45

G45.0 – Vertebro-basilar artery syndromeBillable
G45.1 – Carotid artery syndrome (hemispheric)Billable
G45.2 – Multiple and bilateral precerebral artery syndromesBillable
G45.3 – Amaurosis fugaxBillable
G45.4 – Transient global amnesiaBillable
G45.8 – Other transient cerebral ischemic attacks and related syndromesBillable

Frequently asked questions

What is ICD-10 code G45.9?

G45.9 is the ICD-10-CM code for transient cerebral ischemic attack, unspecified, in the block G40-G47 (Episodic and paroxysmal disorders).

Is G45.9 a billable code?

Yes. G45.9 is a billable/specific code that can be used to indicate a diagnosis for reimbursement purposes.

What category does G45.9 belong to?

It belongs to category G45 – Transient cerebral ischemic attacks and related syndromes.

Source: CDC/NCHS ICD-10-CM FY2027 code files, tabular list and index. Reference only – code assignment must follow the official ICD-10-CM guidelines and documentation in the medical record.