Is G23 a billable ICD-10-CM code?

No. G23 is a non-billable header code. Code to a higher level of specificity using one of its child codes.

Where does G23 sit in the tabular list?

Diseases of the nervous system (G00-G99), in the block Extrapyramidal and movement disorders (G20-G26).

G23

G23 — Other degenerative diseases of basal ganglia

Non-billable headerICD-10-CM

G23 is a non-billable header ICD-10-CM code for other degenerative diseases of basal ganglia. It cannot be billed on its own: choose one of the more specific child codes below.

Excludes2 — not included here, but may coexist

The excluded condition is not part of this code, but a patient can have both. You may code both.

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

Risk adjustment

G23 does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.

Code to one of these instead G23

6 child codes. Green means billable.

Questions about G23

Is G23 a billable ICD-10-CM code?: No. G23 is a non-billable header code. Code to a higher level of specificity using one of its child codes.
Where does G23 sit in the tabular list?: Diseases of the nervous system (G00-G99), in the block Extrapyramidal and movement disorders (G20-G26).