Other drug induced secondary parkinsonism

This code represents a form of parkinsonism that develops as a side effect of medication, excluding neuroleptic-induced parkinsonism. It involves the presence of Parkinson's disease-like symptoms, such as tremor, rigidity, and bradykinesia, directly attributable to a drug other than typical antipsychotics.

Use this code when a patient presents with parkinsonian symptoms clearly linked to the use of a specific medication, and that medication is not a neuroleptic. Documentation should explicitly state "drug-induced parkinsonism" and identify the causative drug, ruling out idiopathic Parkinson's disease.

• Always identify the specific drug causing the parkinsonism, if known, using an additional code from T36-T50 with the appropriate fifth or sixth character for adverse effect.
• Differentiate from G21.0 (Malignant neuroleptic syndrome) and G21.11 (Neuroleptic induced parkinsonism) which are specific to neuroleptic agents.
• Ensure documentation clearly distinguishes drug-induced parkinsonism from idiopathic Parkinson's disease (G20).