ICD-10-CM 2027 diagnosis code

G46Vascular syndromes of brain in cerebrovascular diseases

Not billable — use a more specific code

G46 is a header code, so it can't be reported by itself. Choose one of the 9 more specific codes beneath it.

Code unchanged since ICD-10-CM took effect on October 1, 2015. Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data

About G46

G46 is the ICD-10-CM diagnosis code for vascular syndromes of brain in cerebrovascular diseases. It belongs to block G40-G47 (episodic and paroxysmal disorders) and chapter 6 (diseases of the nervous system). It is a header code, so it can't be reported by itself; one of its 9 subcodes must be used instead.

To report this condition, pick the subcode that matches the documentation: G46.0 (syndrome), G46.1 (syndrome), G46.2 (syndrome), G46.3 (syndrome), G46.4 (syndrome), G46.5 (syndrome), G46.6 (syndrome), G46.7 (syndromes) and 1 more.

Code first: underlying cerebrovascular disease (I60-I69).

It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.

Specific codes under G46

Coding notes

Code firstSequence the underlying condition first

underlying cerebrovascular disease (I60-I69)

Notes that apply from higher levels

Instructions written at a parent level also apply to G46.

Broader instructions also apply from Chapter 6: Diseases of the nervous system.

Code history

2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027

FY2016 (effective 10/1/2015): Added (first year of ICD-10-CM)
No changes since FY2016.

Common questions about G46

Is G46 billable?: No. G46 is a header code. Report one of its more specific subcodes instead.