G21.3
BillablePostencephalitic parkinsonism
Postencephalitic parkinsonism
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 periodP04-P96
- •certain infectious and parasitic diseasesA00-B99
- •complications of pregnancy, childbirth and the puerperiumO9A)O00
- •congenital malformations, deformations, and chromosomal abnormalitiesQ00-Q99
- •endocrine, nutritional and metabolic diseasesE00-E88
- •injury, poisoning and certain other consequences of external causesS00-T88
- •neoplasmsC00-D49
- •symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classifiedR00-R94
Related Codes(6)
ICD-11 Equivalents(1)
ICD-11 Equivalents
View full mappingCorresponding ICD-11 codes from the WHO crosswalk mapping
Also Known As / Clinical Terms(59)
SNOMED CT
UMLS
- ENCEPH LETHARGICA TYPE PARKINSONISMC0030568
- Economo-Type Parkinsonism, PostencephaliticC0030568
- Encephalitis Lethargica Type ParkinsonismC0030568
- PARKINSON DIS POST ENCEPHC0030568
- PARKINSON DIS POSTENCEPHC0030568
- PARKINSONIAN SYNDROME POSTENCEPC0030568
- PARKINSONISM POSTENCEPHC0030568
- POST ENCEPH PARKINSON DISC0030568
- POSTENCEPH ECONOMO TYPE PARKINSONISMC0030568
- POSTENCEPH PARKINSON DISC0030568
- POSTENCEPH PARKINSONISMC0030568
- Parkinson Disease, Post EncephaliticC0030568
- Parkinson Disease, Post-EncephaliticC0030568
- Parkinson Disease, PostencephaliticC0030568
- Parkinsonian Syndrome, PostencephalitisC0030568
- Parkinsonism post encephaliticC0030568
- Parkinsonism, PostencephaliticC0030568
- Parkinsonism, Postencephalitic Economo-TypeC0030568
- Post Encephalitic Parkinson DiseaseC0030568
- Post-Encephalitic Parkinson DiseaseC0030568
- Postencephalitic Economo Type ParkinsonismC0030568
- Postencephalitic Economo-Type ParkinsonismC0030568
- Postencephalitic Parkinson DiseaseC0030568
- Postencephalitic ParkinsonismC0030568
- Postencephalitic parkinsonismC0030568
- Postencephalitic parkinsonism (disorder)C0030568
- Postencephalitis Parkinsonian SyndromeC0030568
- von Economo Encephalitis Type ParkinsonismC0030568
Clinical Terms
- Postencephalitic Economo Type Parkinsonism
- Encephalitis Lethargica Type Parkinsonism
- Parkinson Disease, Post-Encephalitic
- Post-encephalitic syndrome
- Post Encephalitic Parkinson Disease
- POST ENCEPH PARKINSON DIS
- Economo-Type Parkinsonism, Postencephalitic
- Parkinsonism post encephalitic
- POSTENCEPH PARKINSONISM
- PARKINSON DIS POSTENCEPH
- Post-encephalitis syndrome
- ENCEPH LETHARGICA TYPE PARKINSONISM
- PARKINSON DIS POST ENCEPH
- Postencephalitis Parkinsonian Syndrome
- Postencephalitic Parkinson Disease
- Postencephalitic Economo-Type Parkinsonism
- PARKINSONIAN SYNDROME POSTENCEP
- von Economo Encephalitis Type Parkinsonism
- Parkinson Disease, Postencephalitic
- POSTENCEPH PARKINSON DIS
- Parkinson Disease, Post Encephalitic
- POSTENCEPH ECONOMO TYPE PARKINSONISM
- Post-Encephalitic Parkinson Disease
- Parkinsonism, Postencephalitic
- Parkinsonism, Postencephalitic Economo-Type
- Parkinsonian Syndrome, Postencephalitis
- PARKINSONISM POSTENCEPH
- Postencephalitic parkinsonism (disorder)
Frequently Asked Questions
What is the ICD-10 code for postencephalitic parkinsonism?
The ICD-10-CM code for postencephalitic parkinsonism is G21.3. The full clinical description is "Postencephalitic parkinsonism". G21.3 is a billable/specific code that can be used on insurance claims and medical billing.
What does ICD-10 code G21.3 mean?
ICD-10-CM code G21.3 represents “Postencephalitic parkinsonism”. It is classified under Chapter 6: Diseases of the Nervous System and is a billable/specific code that can be used on a claim.
Is G21.3 a billable code?
Yes, G21.3 is a billable/specific ICD-10-CM code and can be used to indicate a diagnosis on a medical claim.
What chapter is G21.3 in?
G21.3 is in Chapter 6: Diseases of the Nervous System (codes G00-G99).
What codes cannot be used with G21.3?
G21.3 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 SNOMED CT codes does G21.3 map to?
G21.3 maps to 2 SNOMED CT concepts: 40673001, 19972008. SNOMED CT is a clinical terminology used in electronic health records.
What are the UMLS CUIs for G21.3?
G21.3 is linked to 1 UMLS Concept Unique Identifier: C0030568. The UMLS (Unified Medical Language System) integrates multiple biomedical vocabularies maintained by the U.S. National Library of Medicine.
How does G21.3 relate to ICF functioning codes?
ICF (International Classification of Functioning, Disability and Health) codes describe how conditions like postencephalitic parkinsonism affect a person's functioning: body functions, activities, participation, and environmental factors. AutoICD provides ICF Core Sets for 12+ conditions and can map clinical text to ICF categories automatically. Browse the ICF directory to explore functioning codes.
What is the ICD-11 equivalent of G21.3?
G21.3 maps to the ICD-11 code: 8A00.2Z (Secondary parkinsonism, unspecified).
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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.