tardive dyskinesia [L, tardus, late; Gk, dys, difficult, kinesis, movement] , an abnormal condition characterized by involuntary repetitive movements of the muscles of the face, limbs, and trunk. This disorder most commonly affects older people who have been treated for extended periods with antipsychotics but can be caused by antidopaminergic medication. The involuntary movements associated with the condition may slacken or disappear after weeks or months and have been significantly reduced in some individuals by the administration of cholinergic drugs.
