G21.9

Approximate Synonyms

• Parkinsons disease, secondary

• Secondary 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)

Details

• G21.9 is a billable/specific ICD-10-CM code that can be used to indicate a diagnosis for reimbursement purposes.

• The 2023 edition of ICD-10-CM G21.9 became effective on October 1, 2022.

• This is the American ICD-10-CM version of G21.9 – other international versions of ICD-10 G21.9 may differ.