Movement Disorder Associated with Antipsychotic Drugs: The Tardive Syndromes

The term tardive dyskinesia, even when properly limited to abnormal involuntary movements occurring in individuals receiving chronic antipsychotic drugs, may still be used to refer to a range of qualitatively different motor phenomena at various body sites. Within this broad syndrome, distinct syndromes have been delineated that are phenomenologically and possibly pathophysiologically distinct. The evidence is reviewed for the existence of tardive dystonia and chronic akathisia as separate clinical entities, and for the validity of two regional subsyndromes of tardive dyskinesia, oro-facial and trunk and limb choreiform dyskinesia. Each of these tardive syndromes is discussed in terms of clinical features, pharmacological response and pathophysiology. Separate assessment of these subsyndromes is suggested in studies of tardive dyskinesia, particularly those investigating drug treatment, risk factors and natural history.