Diseases of the nervous system (G00–G99) ICD-10-CM
Chapter 6 of the ICD-10-CM classification spans codes G00–G99 and contains 932 diagnosis codes for diseases of the nervous system, of which 700 are billable. The chapter is organized into 11 sections listed below, each linking to its code ranges and individual codes.
Chapter Coding Notes
Excludes2: 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)
Sections in This Chapter 11 ranges · 932 codes
The info icon previews the code ranges inside each row and its instructional notations from the official Tabular List.
About Chapter 6
ICD-10-CM Chapter 6 (G00–G99) codes cover a wide range of diseases and disorders of the nervous system. These codes are used to classify conditions affecting the brain, spinal cord, peripheral nerves, and associated structures.
This chapter includes diagnoses related to infections like meningitis and encephalitis, degenerative diseases such as Parkinson’s and Alzheimer’s, demyelinating diseases including multiple sclerosis, and nerve root disorders like radiculopathy. It also encompasses various neuropathies, epileptic disorders, and neurovascular conditions like stroke. The codes help healthcare professionals accurately document nervous system diseases, aiding in effective treatment planning and tracking of neurological health conditions.
Questions About This Page
How many codes are in the G00-G99 range?
The G00-G99 range contains 932 ICD-10-CM diagnosis codes in FY 2026. 700 of them are billable, and the rest are category headers that organize the chapter.
What conditions does G00-G99 cover?
The range covers diseases of the nervous system. The sections listed above break it into groups of related conditions, and each one links to its own page with the full code list.
Related References
Source: CMS FY 2026 ICD-10-CM Tabular List and order file, effective October 1, 2025 through September 30, 2026.
