Secondary parkinsonism G21- >

Type 1 Excludes
Type 1 Excludes Help
A type 1 excludes note is a pure excludes. It means "not coded here". A type 1 excludes note indicates that the code excluded should never be used at the same time as G21. A type 1 excludes note is for used for when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.
  • dementia with Parkinsonism (
    ICD-10-CM Diagnosis Code G31.83

    Dementia with Lewy bodies

      2016 2017 2018 2019 2020 Billable/Specific Code
    Applicable To
    • Dementia with Parkinsonism
    • Lewy body dementia
    • Lewy body disease
  • Huntington's disease (
    ICD-10-CM Diagnosis Code G10

    Huntington's disease

      2016 2017 2018 2019 2020 Billable/Specific Code
    Applicable To
    • Huntington's chorea
    • Huntington's dementia
    Code Also
    • dementia in other diseases classified elsewhere without behavioral disturbance (F02.80)
  • Shy-Drager syndrome (
    ICD-10-CM Diagnosis Code G90.3

    Multi-system degeneration of the autonomic nervous system

      2016 2017 2018 2019 2020 Billable/Specific Code
    Applicable To
    • Neurogenic orthostatic hypotension [Shy-Drager]
    Type 1 Excludes
    • orthostatic hypotension NOS (I95.1)
  • syphilitic Parkinsonism (
    ICD-10-CM Diagnosis Code A52.19

    Other symptomatic neurosyphilis

      2016 2017 2018 2019 2020 Billable/Specific Code
    Applicable To
    • Syphilitic parkinsonism
Clinical Information
  • Conditions which feature clinical manifestations resembling primary parkinson disease that are caused by a known or suspected condition. Examples include parkinsonism caused by vascular injury, drugs, trauma, toxin exposure, neoplasms, infections and degenerative or hereditary conditions. Clinical features may include bradykinesia, rigidity, parkinsonian gait, and masked facies. In general, tremor is less prominent in secondary parkinsonism than in the primary form. (from Joynt, Clinical Neurology, 1998, ch38, pp39-42)
  • G21 Secondary parkinsonism
    • G21.0 Malignant neuroleptic syndrome
    • G21.1 Other drug-induced secondary parkinsonism
      • G21.11 Neuroleptic induced parkinsonism
      • G21.19 Other drug induced secondary parkinsonism
    • G21.2 Secondary parkinsonism due to other external agents
    • G21.3 Postencephalitic parkinsonism
    • G21.4 Vascular parkinsonism
    • G21.8 Other secondary parkinsonism
    • G21.9 Secondary parkinsonism, unspecified