2026 ICD-10-CM Diagnosis Code G99Other disorders of nervous system in diseases classified elsewhere

ICD-10-CM Codes›G00–G99›G89-G99›G99

ICD-10-CM G99
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

G99 is a non-billable ICD-10-CM category code for other disorders of nervous system in diseases classified elsewhere, so it cannot be submitted on claims. Use a more specific code from this category instead, such as G99.0, G99.2, and G99.8.

Code Identity

ICD-10-CM Code
G99
Billable Status
No — Non-Billable Category
Code Describes
Other disorders of nervous system in diseases classified elsewhere
Chapter
G89-G99
Other disorders of the nervous system

Code Classification

ChapterG00–G99Diseases of the nervous system
SectionG89-G99Other disorders of the nervous system
CategoryG99Other disorders of nervous system in diseases classified elsewhere
This CodeG99Other disorders of nervous system in diseases classified elsewhere

Specific Coding for Oth disorders of nervous system in diseases classd elswhrOverview

Non-specific codes like G99 require more characters. Use one of these billable codes instead:

  • Use G99.0 for Autonomic neuropathy in diseases classified elsewhere

  • Use G99.2 for Myelopathy in diseases classified elsewhere

  • Use G99.8 for Other specified disorders of nervous system in diseases classified elsewhere

Patient EducationClinical

Neurologic Diseases

The brain, spinal cord, and nerves make up the nervous system. Together they control all the workings of the body. When something goes wrong with a part of your nervous system, you can have trouble moving, speaking, swallowing, breathing, or learning. You can also have problems with your memory, senses, or mood.

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 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About G99Overview

Is G99 a billable code?

No. This is a category header that groups the codes for other disorders of nervous system in diseases classified elsewhere, and headers cannot be submitted on claims. Claims for other disorders of nervous system in diseases classified elsewhere need a more specific code from this category, such as G99.0, G99.2, and G99.8.