G31.8 – Other specified degenerative diseases of nervous system
ICD-10-CM 2027 diagnosis code · Other degenerative diseases of the nervous system
- Code
G31.8(claims format:G318)- Description
- Other specified degenerative diseases of nervous system
- Billable
- No – use a more specific code below
- Valid for
- Dates of service October 1, 2026 – September 30, 2027 (FY2027)
- Chapter
- 6. Diseases of the nervous system (G00-G99)
- Block
- G30-G32 Other degenerative diseases of the nervous system
- Parent codes
- G31
Billable codes under G31.8
G31.8 is a header code and cannot be used on claims. Choose the most specific code:
- G31.80 – Leukodystrophy, unspecifiedBillable
- G31.81 – Alpers diseaseBillable
- G31.82 – Leigh's diseaseBillable
- G31.83 – Neurocognitive disorder with Lewy bodiesBillable
- G31.84 – Mild cognitive impairment of uncertain or unknown etiologyBillable
- G31.85 – Corticobasal degenerationBillable
- G31.86 – Alexander diseaseBillable
- G31.87 – Primary progressive apraxia of speechBillable
- G31.89 – Other specified degenerative diseases of nervous systemBillable
Notes inherited from parent codes
Instructional notes at a category or block level apply to every code below it.
G31 – Other degenerative diseases of nervous system, not elsewhere classified
- Reye's syndrome (G93.7)
- code, if applicable, for codes G31.0-G31.83, G31.85-G31.9, to identify:
- dementia with anxiety (F02.84, F02.A4, F02.B4, F02.C4)
- dementia with behavioral disturbance (F02.81-, F02.A1-, F02.B1-, F02.C1-)
- dementia with mood disturbance (F02.83, F02.A3, F02.B3, F02.C3)
- dementia with psychotic disturbance (F02.82, F02.A2, F02.B2, F02.C2)
- dementia without behavioral disturbance (F02.80, F02.A0, F02.B0, F02.C0)
- mild neurocognitive disorder due to known physiological condition (F06.7-)
Related codes in G31
Frequently asked questions
What is ICD-10 code G31.8?
G31.8 is the ICD-10-CM code for other specified degenerative diseases of nervous system, in the block G30-G32 (Other degenerative diseases of the nervous system).
Is G31.8 a billable code?
No. G31.8 is a header code with more specific child codes; report one of the billable codes listed above.
What category does G31.8 belong to?
It belongs to category G31 – Other degenerative diseases of nervous system, not elsewhere classified.
Source: CDC/NCHS ICD-10-CM FY2027 code files, tabular list and index. Reference only – code assignment must follow the official ICD-10-CM guidelines and documentation in the medical record.