Other secondary parkinsonism

This code signifies a form of parkinsonism that arises as a symptom of another underlying condition, rather than idiopathic Parkinson's disease. It encompasses various etiologies leading to parkinsonian symptoms, such as bradykinesia, rigidity, tremor, and postural instability, that are not otherwise specified as drug-induced, vascular, or due to other specific causes.

Apply this code when documentation clearly indicates parkinsonian features secondary to a diagnosed condition not classified elsewhere, such as certain metabolic disorders, infections, or neurodegenerative diseases where the specific type of secondary parkinsonism is not explicitly defined. Supporting documentation should detail the parkinsonian symptoms and the identified underlying cause.

• Always sequence the underlying condition causing the secondary parkinsonism first, followed by this code.
• Differentiate carefully from drug-induced parkinsonism (G21.1x) and vascular parkinsonism (G21.4).
• Ensure the medical record specifies the secondary nature of the parkinsonism and rules out idiopathic Parkinson's disease (G20).