712 Medication-Induced Movement Disorders
Tardive Dyskinesia
333.85 (G24.01) Tardive Dyskinesia
Involuntary athetoid or chorei form movements (lasting at le ast a few weeks) generally of
the tongue, lower face and jaw, and extremit ies (but sometimes involving the pharyngeal,
diaphragmatic, or trunk muscles) developing in association with the use of a neuroleptic
medication for at least a few months.
Symptoms may develop after a shorter period  of medication use in older persons. In
some patients, movements of this type may ap pear after discontinuation, or after change
or reduction in dosage, of neuroleptic medica tions, in which case the condition is called
neuroleptic withdrawal -emergent dyskinesia.  Because withdrawal-emergent dyskinesia is
usually time-limited, lasting less than 4–8 week s, dyskinesia that persists beyond this win-
dow is considered to be tardive dyskinesia.
Tardive Dystonia
Tardive Akathisia
333.72 (G24.09) Tardive Dystonia
333.99 (G25.71) Tardive Akathisia
Tardive syndrome involving other types of movement problems, such as dystonia or
akathisia, which are distinguished by their late  emergence in the course of treatment and
their potential persistence for months to years,  even in the face of neuroleptic discontinu-
ation or dosage reduction.
Medication-Induced Postural Tremor
333.1 (G25.1) Medication-Induced Postural Tremor
Fine tremor (usually in the range of 8–12 Hz) occurring during attempts to maintain a pos-