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  2. ICD-10-CM Codes List
  3. G00–G99
  4. G20-G26
  5. Parkinson's disease (G20)

Parkinson's disease (G20)

The ICD-10 code for Parkinson's disease is primarily G20, with detailed subcodes distinguishing cases with or without dyskinesia and fluctuations. These codes facilitate precise classification of Parkinson's disease and related parkinsonian disorders in medical records and billing.

The main code G20 covers Parkinson's disease in general, while subcategories such as G20.A1 represent Parkinson's disease without dyskinesia and fluctuations, including variations like juvenile or young-onset Parkinson's and conditions like dementia due to Parkinson's disease. G20.A2 identifies Parkinson's disease without dyskinesia but with motor fluctuations, often described as "off-periods" not responsive to oral treatments. Codes G20.B1 and G20.B2 cover Parkinson's disease with dyskinesia, differentiated by the presence or absence of fluctuations. Additionally, G20.C captures unspecified parkinsonism, encompassing a broad range of related syndromes such as Parkinsonian tremor and atypical parkinsonism. This structured coding helps healthcare providers document various Parkinson's presentations accurately and supports effective patient management and analytics.

Instructional Notations

Inclusion Terms

These terms are the conditions for which that code is to be used. The terms may be synonyms of the code title, or, in the case of "other specified" codes, the terms are a list of the various conditions assigned to that code. The inclusion terms are not necessarily exhaustive. Additional terms found only in the Alphabetic Index may also be assigned to a code.

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

Use Additional Code

The “use additional code” indicates that a secondary code could be used to further specify the patient’s condition. This note is not mandatory and is only used if enough information is available to assign an additional code.