G21.0: Malignant neuroleptic syndrome
G21.0 is the billable ICD-10-CM diagnosis code for Malignant neuroleptic syndrome. It is a fully specified code, so it can be reported on a claim (subject to clinical documentation and your payer's rules).
Frequently asked questions
What is ICD-10-CM code G21.0?
G21.0 is the ICD-10-CM diagnosis code for Malignant neuroleptic syndrome. It belongs to category G21 (Secondary parkinsonism).
Is G21.0 a billable code?
Yes. G21.0 is a billable, fully specified ICD-10-CM code, so it can be used on a claim (subject to documentation and payer rules).
What category does G21.0 belong to?
G21.0 is part of ICD-10-CM category G21 — Secondary parkinsonism, which has 16 billable codes.
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Informational only, not coding or medical advice. Verify against the official ICD-10-CM (FY2026) and your payer's guidelines.
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