Is ICD-10-CM code G23 billable?

No, G23 (Other degenerative diseases of basal ganglia) is a non-billable ICD-10-CM code. It must be coded to a more specific subcategory before it can be used for reimbursement.

What chapter does ICD-10-CM code G23 belong to?

G23 belongs to Chapter 6 of the ICD-10-CM tabular list: G00–G99 (Diseases of the Nervous System).

G23Not billable, use a more specific code below

Other degenerative diseases of basal ganglia

In Extrapyramidal and movement disorders (G20-G26), chapter 6: Diseases of the Nervous System

6 billable codes under G23: all are a CC; all map to HCC 199 (Parkinson and Other Degenerative Disease of Basal Ganglia).A CC or MCC (major CC) is a secondary diagnosis that raises the MS-DRG payment. An HCC counts toward a Medicare Advantage patient's risk score.

Instructional notes

Excludes2: not included here, code separately if applicable

multi-system degeneration of the autonomic nervous system (G90.3)

Official coding guidelines

From the ICD-10-CM Official Guidelines for Coding and Reporting, FY 2027 (CMS and NCHS). Links open the PDF at the right page.

Covers default dominant or nondominant side for hemiplegia and monoplegia, and use and sequencing of G89 pain codes, including postoperative, chronic, and neoplasm-related pain.

Dominant/nondominant side (page 45)
Pain - Category G89 (page 45)

Read Section I.C.6 (page 45)

All codes under G23

G23 can't be used on a claim. Pick a billable code below; grey headings group them.

G23 MS-DRGs

As the principal diagnosis, all 6 billable codes under G23 group to MS-DRG 056 or 057 (v44.0). Which one applies depends on procedures performed, secondary diagnoses (CC/MCC), and the patient's age and discharge status.

About the condition

Plain-language background from MedlinePlus (National Library of Medicine), not coding guidance.

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. Your nerves take in information from your senses and send it to the brain to be processed. Your brain and nerves also communicate to help you move and to control your body's functions.

Code history

Valid since FY2016, when ICD-10-CM took effect on October 1, 2015. No changes since.