G21
Non-billableSecondary parkinsonism
Secondary parkinsonism
This is a header/category code. For billing purposes, use a more specific child code from the list below.
Coding Notes
Excludes 1
Codes that cannot be used together with this code (mutual exclusion)
Excludes 2
Conditions not included here, but the patient may have both
- 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)
Child Codes (7)
G21.0Malignant neuroleptic syndrome
G21.1Other drug-induced secondary parkinsonism
G21.2Secondary parkinsonism due to other external agents
G21.3Postencephalitic parkinsonism
G21.4Vascular parkinsonism
G21.8Other secondary parkinsonism
G21.9Secondary parkinsonism, unspecified
Also Known As / Clinical Terms
UMLS
- Disorders presenting primarily with parkinsonismC0030569
- PARKINSON DIS SECONDC0030569
- PARKINSON DIS SYMPTOMATICC0030569
- PARKINSONISM SECONDC0030569
- Parkinson Disease, SecondaryC0030569
- Parkinson Disease, SymptomaticC0030569
- Parkinsonism, SecondaryC0030569
- Parkinsonism, SymptomaticC0030569
- SECOND PARKINSONISMC0030569
- SYMPTOMATIC PARKINSON DISC0030569
- Secondary Parkinson DiseaseC0030569
- Secondary Parkinson diseaseC0030569
- Secondary Parkinson's diseaseC0030569
- Secondary ParkinsonismC0030569
- Secondary parkinsonismC0030569
- Secondary parkinsonism (disorder)C0030569
- Secondary parkinsonism, unspecifiedC0030569
- Symptomatic Parkinson DiseaseC0030569
- Symptomatic ParkinsonismC0030569
- Symptomatic parkinsonismC0030569
- Symptomatic parkinsonism (disorder)C0030569
- parkinson's disease secondaryC0030569
- parkinsonism secondaryC0030569
- secondary parkinsonismC0030569
Frequently Asked Questions
What is ICD-10 code G21?
ICD-10-CM code G21 represents "Secondary parkinsonism". It is a non-billable header code — use a more specific child code for billing purposes.
Is G21 a billable code?
No, G21 is a non-billable header code. You need to use one of its more specific child codes for billing. There are 7 child codes under G21.
What chapter is G21 in?
G21 is in Chapter 6: Diseases of the Nervous System (codes G00-G99).
What codes cannot be used with G21?
G21 has Excludes1 notes indicating codes that cannot be used together with it, including: Huntington's disease (G10); neurocognitive disorder with Lewy bodies (G31.83); Shy-Drager syndrome (G90.3); and 1 more.
What are the subcategories under G21?
G21 has 7 child codes, including: G21.0 (Malignant neuroleptic syndrome), G21.1 (Other drug-induced secondary parkinsonism), G21.2 (Secondary parkinsonism due to other external agents), G21.3 (Postencephalitic parkinsonism), and 3 more.
What are the UMLS CUIs for G21?
G21 is linked to 1 UMLS Concept Unique Identifier: C0030569. The UMLS (Unified Medical Language System) integrates multiple biomedical vocabularies maintained by the U.S. National Library of Medicine.
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Includes SNOMED Clinical Terms® (SNOMED CT®) used by permission of SNOMED International. Includes content from the UMLS Metathesaurus, courtesy of the U.S. National Library of Medicine.