2027 ICD-10-CM Diagnosis Code G23Other degenerative diseases of basal ganglia

ICD-10-CM Codes›G00–G99›G20-G26›G23

ICD-10-CM G23
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

G23 is a non-billable ICD-10-CM category code for other degenerative diseases of basal ganglia, so it cannot be submitted on claims. Use a more specific code from this category instead, such as G23.0, G23.1, G23.2, and G23.3.

Code Identity

ICD-10-CM Code
G23
Billable Status
No — Non-Billable Category
Code Describes
Other degenerative diseases of basal ganglia
Short Description
Other degenerative diseases of basal ganglia
Same as the full description in the CMS dataset.
Chapter
G20-G26
Extrapyramidal and movement disorders

Code Classification

ChapterG00–G99Diseases of the nervous system
SectionG20-G26Extrapyramidal and movement disorders
CategoryG23Other degenerative diseases of basal ganglia
This CodeG23Other degenerative diseases of basal ganglia

Specific Coding for Other degenerative diseases of basal gangliaOverview

Non-specific codes like G23 require more characters. Use one of these billable codes instead:

  • Use G23.0 for Hallervorden-Spatz disease

  • Use G23.1 for Progressive supranuclear ophthalmoplegia [Steele-Richardson-Olszewski]

  • Use G23.2 for Striatonigral degeneration

  • Use G23.3 for Hypomyelination with atrophy of the basal ganglia and cerebellum

  • Use G23.8 for Other specified degenerative diseases of basal ganglia

  • Use G23.9 for Degenerative disease of basal ganglia, unspecified

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to G23: its own notes plus those printed at Chapter 6. A note printed at a category, block or chapter applies to every code under it.

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.

On G23 itself
  • multi-system degeneration of the autonomic nervous system (G90.3)
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 G23, its category, or a range that includes it.

Excludes1 1

These codes carry an Excludes1 note naming G23: they are not reported together with it, unless the two conditions are unrelated.

  • R25 Abnormal involuntary movements
    specific movement disorders (G20-G26) names G20-G26, which includes this code

Excludes2 1

These codes carry an Excludes2 note naming G23: its condition is not part of those codes, and both may be reported when the patient has both.

  • F98.4 Stereotyped movement disorders
    movement disorders of organic origin (G20-G25) names G20-G25, which includes this code

Patient EducationClinical

Brain Diseases

Your brain is the control center of your body. It controls your thoughts, memory, speech, and movement. It regulates the function of many organs. It's part of your nervous system, which also includes your spinal cord and peripheral nerves. The nervous system sends signals between your brain and the rest of the body.

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 G23Overview

What is the ICD-10 code for other degenerative diseases of basal ganglia?

G23 is the ICD-10-CM category for other degenerative diseases of basal ganglia, but it is a non-billable header: claims need a more specific code from this category, listed on this page.

Is G23 (Other degenerative diseases of basal ganglia) a billable code?

No. This is a category header that groups the codes for other degenerative diseases of basal ganglia, and headers cannot be submitted on claims. Claims for other degenerative diseases of basal ganglia need a more specific code from this category, such as G23.0, G23.1, and G23.2.