G21.3Billable
Postencephalitic parkinsonism
- Chapter
- 6. Diseases of the nervous system
- Category
- G21
- Effective date
- October 1, 2026
Related codes in category G21
G21Secondary parkinsonismG21.0Malignant neuroleptic syndromeYesG21.1Other drug-induced secondary parkinsonismG21.11Neuroleptic induced parkinsonismYesG21.19Other drug induced secondary parkinsonismYesG21.2Secondary parkinsonism due to other external agentsYesG21.4Vascular parkinsonismYesG21.8Other secondary parkinsonismYesG21.9Secondary parkinsonism, unspecifiedYes
Frequently asked questions
What is ICD-10 code G21.3?
G21.3 is an ICD-10-CM diagnosis code for Postencephalitic parkinsonism.
Is G21.3 a billable code?
Yes. G21.3 is billable and specific enough to be used on a claim.
What ICD-10-CM chapter is G21.3 in?
G21.3 falls under Chapter 6: Diseases of the nervous system.
When did G21.3 become effective?
G21.3 has been effective since October 1, 2026, per the CMS/CDC ICD-10-CM annual release.
What other codes are related to G21.3?
G21.3 belongs to category G21, which includes 9 other codes — see the related codes list on this page.
ICD-10-CM data maintained by CDC/CMS (public domain). Always verify codes with authoritative sources before making coding or billing decisions.