2019 ICD-10-CM Diagnosis Code G20

Parkinson's disease

    2016 2017 2018 2019 Billable/Specific Code
  • G20 is a billable/specific ICD-10-CM code that can be used to indicate a diagnosis for reimbursement purposes.
  • The 2019 edition of ICD-10-CM G20 became effective on October 1, 2018.
  • This is the American ICD-10-CM version of G20 - other international versions of ICD-10 G20 may differ.
Applicable To
  • Hemiparkinsonism
  • Idiopathic Parkinsonism or Parkinson's disease
  • Paralysis agitans
  • Parkinsonism or Parkinson's disease NOS
  • Primary Parkinsonism or Parkinson's disease
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 G20. 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 Billable/Specific Code
    Applicable To
    • Dementia with Parkinsonism
    • Lewy body dementia
    • Lewy body disease
    G31.83
    )
The following code(s) above G20 contain annotation back-references
Annotation Back-References
In this context, annotation back-references refer to codes that contain:
  • Applicable To annotations, or
  • Code Also annotations, or
  • Code First annotations, or
  • Excludes1 annotations, or
  • Excludes2 annotations, or
  • Includes annotations, or
  • Note annotations, or
  • Use Additional annotations
that may be applicable to G20:
  • G00-G99
    2019 ICD-10-CM Range G00-G99

    Diseases of the nervous system

    Type 2 Excludes
    • 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)
    Diseases of the nervous system
Approximate Synonyms
  • Dementia associated with parkinson's disease
  • Dementia in parkinsons disease
  • Parkinsonism
  • Parkinsons disease
  • Restrictive lung disease due to parkinsons disease
  • Restrictive lung mechanics due to parkinsons disease
Clinical Information
  • A disease characterized as a progressive motor disability manifested by tremors, shaking, muscular rigidity, and lack of postural reflexes.
  • A progressive degenerative disorder of the central nervous system characterized by loss of dopamine producing neurons in the substantia nigra and the presence of lewy bodies in the substantia nigra and locus coeruleus. Signs and symptoms include tremor which is most pronounced during rest, muscle rigidity, slowing of the voluntary movements, a tendency to fall back, and a mask-like facial expression.
  • A progressive disorder of the nervous system marked by muscle tremors, muscle rigidity, decreased mobility, stooped posture, slow voluntary movements, and a mask-like facial expression.
  • A progressive, degenerative neurologic disease characterized by a tremor that is maximal at rest, retropulsion (i.e. A tendency to fall backwards), rigidity, stooped posture, slowness of voluntary movements, and a masklike facial expression. Pathologic features include loss of melanin containing neurons in the substantia nigra and other pigmented nuclei of the brainstem. Lewy bodies are present in the substantia nigra and locus coeruleus but may also be found in a related condition (lewy body disease, diffuse) characterized by dementia in combination with varying degrees of parkinsonism. (Adams et al., Principles of Neurology, 6th ed, p1059, pp1067-75)
  • Parkinson's disease is a disorder that affects nerve cells, or neurons, in a part of the brain that controls muscle movement. In parkinson's, neurons that make a chemical called dopamine die or do not work properly. Dopamine normally sends signals that help coordinate your movements. No one knows what damages these cells. Symptoms of parkinson's disease may include
    • trembling of hands, arms, legs, jaw and face
    • stiffness of the arms, legs and trunk
    • slowness of movement
    • poor balance and coordination
    as symptoms get worse, people with the disease may have trouble walking, talking or doing simple tasks. They may also have problems such as depression, sleep problems or trouble chewing, swallowing or speaking. Parkinson's usually begins around age 60, but it can start earlier. It is more common in men than in women. There is no cure for parkinson's disease. A variety of medicines sometimes help symptoms dramatically.
  • Progressive, degenerative disorder of the nervous system characterized by tremors, rigidity, bradykinesia, postural instability, and gait abnormalities; caused by a loss of neurons and a decrease of dopamine in the basal ganglia.
ICD-10-CM G20 is grouped within Diagnostic Related Group(s) (MS-DRG v36.0):
  • 056 Degenerative nervous system disorders with mcc
  • 057 Degenerative nervous system disorders without mcc

Convert G20 to ICD-9-CM

Code History
  • 2016 (effective 10/1/2015): New code (first year of non-draft ICD-10-CM)
  • 2017 (effective 10/1/2016): No change
  • 2018 (effective 10/1/2017): No change
  • 2019 (effective 10/1/2018): No change
Code annotations containing back-references to G20:
  • Code First: F02
    , R47.82
    ICD-10-CM Diagnosis Code F02

    Dementia in other diseases classified elsewhere

      2016 2017 2018 2019 Non-Billable/Non-Specific Code
    Code First
    • the underlying physiological condition, such as:
    • Alzheimer's (G30.-)
    • cerebral lipidosis (E75.4)
    • Creutzfeldt-Jakob disease (A81.0-)
    • dementia with Lewy bodies (G31.83)
    • dementia with Parkinsonism (G31.83)
    • epilepsy and recurrent seizures (G40.-)
    • frontotemporal dementia (G31.09)
    • hepatolenticular degeneration (E83.0)
    • human immunodeficiency virus [HIV] disease (B20)
    • Huntington's disease (G10)
    • hypercalcemia (E83.52)
    • hypothyroidism, acquired (E00-E03.-)
    • intoxications (T36-T65)
    • Jakob-Creutzfeldt disease (A81.0-)
    • multiple sclerosis (G35)
    • neurosyphilis (A52.17)
    • niacin deficiency [pellagra] (E52)
    • Parkinson's disease (G20)
    • Pick's disease (G31.01)
    • polyarteritis nodosa (M30.0)
    • prion disease (A81.9)
    • systemic lupus erythematosus (M32.-)
    • traumatic brain injury (S06.-)
    • trypanosomiasis (B56.-, B57.-)
    • vitamin B deficiency (E53.8)
    Includes
    • Major neurocognitive disorder in other diseases classified elsewhere
    Type 2 Excludes
    • dementia in alcohol and psychoactive substance disorders (F10-F19, with .17, .27, .97)
    • vascular dementia (F01.5-)
    ICD-10-CM Diagnosis Code R47.82

    Fluency disorder in conditions classified elsewhere

      2016 2017 2018 2019 Billable/Specific Code Manifestation Code
    Applicable To
    • Stuttering in conditions classified elsewhere
    Code First
    • underlying disease or condition, such as:
    • Parkinson's disease (G20)
    Type 1 Excludes
    • adult onset fluency disorder (F98.5)
    • childhood onset fluency disorder (F80.81)
    • fluency disorder (stuttering) following cerebrovascular disease (I69. with final characters -23)

Diagnosis Index entries containing back-references to G20:
  • Dementia (degenerative (primary)) (old age) (persisting) F03.90
    ICD-10-CM Diagnosis Code F03.90

    Unspecified dementia without behavioral disturbance

      2016 2017 2018 2019 Billable/Specific Code Adult Dx (15-124 years)
    Applicable To
    • Dementia NOS
  • Disease, diseased - see also Syndrome
    • Parkinson's G20
  • Hemiparkinsonism G20
  • Paralysis, paralytic (complete) (incomplete) G83.9
    ICD-10-CM Diagnosis Code G83.9

    Paralytic syndrome, unspecified

      2016 2017 2018 2019 Billable/Specific Code
    • agitans G20 - see also Parkinsonism
  • Parkinsonism (idiopathic) (primary) G20
  • Pyramidopallidonigral syndrome G20
  • Syndrome - see also Disease
    • pyramidopallidonigral G20

ICD-10-CM Codes Adjacent To G20
G12.25 Progressive spinal muscle atrophy
G12.29 Other motor neuron disease
G12.8 Other spinal muscular atrophies and related syndromes
G12.9 Spinal muscular atrophy, unspecified
G13 Systemic atrophies primarily affecting central nervous system in diseases classified elsewhere
G13.0 Paraneoplastic neuromyopathy and neuropathy
G13.1 Other systemic atrophy primarily affecting central nervous system in neoplastic disease
G13.2 Systemic atrophy primarily affecting the central nervous system in myxedema
G13.8 Systemic atrophy primarily affecting central nervous system in other diseases classified elsewhere
G14 Postpolio syndrome
G20 Parkinson's disease
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

Reimbursement claims with a date of service on or after October 1, 2015 require the use of ICD-10-CM codes.