2027 ICD-10-CM Diagnosis Code G45Transient cerebral ischemic attacks and related syndromes

ICD-10-CM Codes›G00–G99›G40-G47›G45

ICD-10-CM G45
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

G45 is a non-billable ICD-10-CM category code for transient cerebral ischemic attacks and related syndromes, so it cannot be submitted on claims. Use a more specific code from this category instead, such as G45.0, G45.1, G45.2, and G45.3.

Code Identity

ICD-10-CM Code
G45
Billable Status
No — Non-Billable Category
Code Describes
Transient cerebral ischemic attacks and related syndromes
Short Description
Transient cerebral ischemic attacks and related syndromes
Same as the full description in the CMS dataset.
Chapter
G40-G47
Episodic and paroxysmal disorders

Code Classification

ChapterG00–G99Diseases of the nervous system
SectionG40-G47Episodic and paroxysmal disorders
CategoryG45Transient cerebral ischemic attacks and related syndromes
This CodeG45Transient cerebral ischemic attacks and related syndromes

Specific Coding for Transient cerebral ischemic attacks and related syndromesOverview

Non-specific codes like G45 require more characters. Use one of these billable codes instead:

  • Use G45.0 for Vertebro-basilar artery syndrome

  • Use G45.1 for Carotid artery syndrome (hemispheric)

  • Use G45.2 for Multiple and bilateral precerebral artery syndromes

  • Use G45.3 for Amaurosis fugax

  • Use G45.4 for Transient global amnesia

  • Use G45.8 for Other transient cerebral ischemic attacks and related syndromes

  • Use G45.9 for Transient cerebral ischemic attack, unspecified

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to G45: its own notes plus those printed at Chapter 6. A note printed at a category, block or chapter applies to every code under it.

Excludes1

Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.

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

Excludes2

Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.

From Chapter 6 (G00-G99) Diseases of the nervous system applies to 700 codes
  • certain conditions originating in the perinatal period (P04-P96)
  • certain infectious and parasitic diseases (A00-B99)
  • complications of pregnancy, childbirth and the puerperium (O00-O9A)
  • congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99)
  • endocrine, nutritional and metabolic diseases (E00-E88)
  • injury, poisoning and certain other consequences of external causes (S00-T88)
  • neoplasms (C00-D49)
  • symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)

Source: CMS ICD-10-CM Tabular List. How to read instructional notes.

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name G45, its category, or a range that includes it.

Excludes1 1

These codes carry an Excludes1 note naming G45: they are not reported together with it, unless the two conditions are unrelated.

  • I65 Occlusion and stenosis of precerebral arteries, not resulting in cerebral infarction
    insufficiency, NOS, of precerebral artery (G45.-)

Excludes2 2

These codes carry an Excludes2 note naming G45: its condition is not part of those codes, and both may be reported when the patient has both.

  • Chapter 9 (I00-I99) Diseases of the circulatory system
    transient cerebral ischemic attacks and related syndromes (G45.-)
  • I63.9 Cerebral infarction, unspecified
    transient cerebral ischemic attacks and related syndromes (G45.-)

Patient EducationClinical

Transient Ischemic Attack

A transient ischemic attack (TIA) is a stroke that lasts only a few minutes. It happens when the blood supply to part of the brain is briefly blocked. Symptoms of a TIA are like other stroke symptoms, but do not last as long. They happen suddenly, and include:

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About G45Overview

What is the ICD-10 code for transient cerebral ischemic attacks and related syndromes?

G45 is the ICD-10-CM category for transient cerebral ischemic attacks and related syndromes, but it is a non-billable header: claims need a more specific code from this category, listed on this page.

Is G45 (Transient cerebral ischemic attacks and related syndromes) a billable code?

No. This is a category header that groups the codes for transient cerebral ischemic attacks and related syndromes, and headers cannot be submitted on claims. Claims for transient cerebral ischemic attacks and related syndromes need a more specific code from this category, such as G45.0, G45.1, and G45.2.

Can G45 be reported with P91.0?

Not as a rule. The Excludes1 note on G45 lists "neonatal cerebral ischemia (P91.0)". An Excludes1 note means the excluded code is never reported together with this one; the only exception is when the two conditions are unrelated to each other (Official Guidelines, Section I.A.12.a).