G20

Parkinson's disease

FY2027Chapter 6: Diseases of the nervous system/G20–G26 Extrapyramidal and movement disorders

Non-billable headerNot valid on its own. Use one of the more specific codes under it.

G20 is a non-billable ICD-10-CM code category for parkinson's disease. Report a more specific code from it instead. It is part of the FY2027 code set, effective October 1, 2026. The more specific codes under it are G20.A Parkinson's disease without dyskinesia; G20.B Parkinson's disease with dyskinesia and G20.C Parkinsonism, unspecified. Its coding notes include a Use additional code instruction and 8 Excludes2 entries.

Use additional code

Add the listed code as a secondary code, if known.

This code

Excludes2

Not included here. Both codes may be reported if the patient has both conditions.

Also from chapter/block level (8 notes)
Inherited from Chapter 6 Diseases of the nervous system
  • 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)

Inclusion terms

Conditions classified to this code.

This code
  • Hemiparkinsonism
  • Idiopathic Parkinsonism or Parkinson's disease
  • Paralysis agitans
  • Primary Parkinsonism or Parkinson's disease

More specific codes under G20 3