G31.8

Other specified degenerative diseases of nervous system

Header / non-billable

This code does not map to a risk-adjusting HCC in the loaded models.

Coding notes

Excludes 1 never coded together · Excludes 2 may co-exist

Inherited from G31Oth degenerative diseases of nervous system, NEC
Excludes 2

Reye's syndrome (G93.7)

Use additional

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-)

Inherited from chapter 6Diseases of the nervous system
Excludes 2

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)

Official Guidelines for G31.8

FY 2026 ›