G20.C Parkinsonism, unspecified

✓ Billable ICD-10-CM 2026
Open G20.C in Web App →

The ICD-10-CM code for Parkinsonism, unspecified is G20.C (FY2026). It is a billable, claim-ready diagnosis code.

Classification

Section
G20-G26: Extrapyramidal and movement disorders (G20-G26)
Category G20
8 codes (5 billable)
FY2026 Status
Stable since FY2024

Also Known As

ICD-10-CM Alphabetic Index entries that lead to G20.C:

  • Hemiparkinsonism
  • Parkinsonism (idiopathic) (primary)
  • Pyramidopallidonigral syndrome
  • Parkinsonism (idiopathic) (primary) › dementia
  • Paralysis, paralytic (complete) (incomplete) › agitans
  • Syndrome › pyramidopallidonigral
  • Dementia (degenerative (primary)) (persisting) (unspecified severity) (without behavioral disturbance, psychotic disturbance, mood disturbance, and anxiety) › in (due to) › paralysis agitans
  • Dementia (degenerative (primary)) (persisting) (unspecified severity) (without behavioral disturbance, psychotic disturbance, mood disturbance, and anxiety) › with › Parkinsonism
Excludes1
Not coded here. These conditions should NOT be coded together with G20.C.
  • Parkinson's disease NOS (G20.A1)
  • Parkinson's disease with dyskinesia (G20.B-)
  • Parkinson's disease without dyskinesia (G20.A-)
  • secondary parkinsonism (G21.-)

Inclusion Terms

  • Parkinsonism, NOS

U.S. Hospital Utilization

  • An estimated 11,205 U.S. inpatient stays in 2023 included G20.C among the documented diagnoses.
  • 530 stays listed it as the principal diagnosis.

Source: National Inpatient Sample (NIS), Healthcare Cost and Utilization Project (HCUP), Agency for Healthcare Research and Quality, 2016–2023. National survey-weighted estimates.

Prevalence & Statistics

Official Coding Guidelines

Dominant/nondominant side (TOC entry)

a. Dominant/nondominant side ................................................................................................. 45

— ICD-10-CM Official Guidelines for Coding and Reporting, FY2026, Section I.C.6.a
Pain - Category G89 (TOC entry)

b. Pain - Category G89.............................................................................................................. 45

— ICD-10-CM Official Guidelines for Coding and Reporting, FY2026, Section I.C.6.b

Source: CMS — ICD-10-CM Official Guidelines for Coding and Reporting, FY2026

References

Related Codes

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Reviewed by Prajwal Shrestha, CPC, CRC
Certified Professional Coder (CPC) and Certified Risk Adjustment Coder (CRC) · AAPC Member ID 01997614 · About · Editorial policy · Content last reviewed: 2025-10-01

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