G21
Header — not billableSecondary parkinsonism
The ICD-10 code for secondary parkinsonism is G21.
G21 is a non-billable header code. It groups related conditions but cannot be used on its own for reimbursement — select one of the 7 more specific codes below.
Clinical notes
Excludes1 (not coded here)
An Excludes1 note is a pure exclusion: the excluded condition and this code should never be reported together, because the two conditions cannot occur at the same time (e.g. a congenital form vs. an acquired form of the same disease).
Documentation support
General coding-documentation guidance — not a substitute for payer-specific requirements or professional coding judgment.
- •This is a non-billable header code. Documentation must support a more specific child code before this diagnosis can be reported on a claim.
- •Confirm the excluded condition(s) listed above are not also present — Excludes1 conditions cannot be coded together with this one.
- •As a general rule, code to the highest level of specificity supported by the documentation in the medical record.
Child codes under G21
Related codes in this category
- G20Parkinson's diseasenon-billable header
- G23Other degenerative diseases of basal ganglianon-billable header
- G24Dystonianon-billable header
- G25Other extrapyramidal and movement disordersnon-billable header
- G26Extrapyramidal and movement disorders in diseases classified elsewhere
- G21Secondary parkinsonismnon-billable header