The current status of tardive dystonia

Tardive dystonia (TDt), a persistent dystonia associated with exposure to n eurolept ic drugs, is an uncommon disorder. It differs from tardive dyskine sia (TDk) in epidemiology, clinical features, risk factors, pathophysiology , course, prognosis, and treatment outcome. TDt seems to develop faster and is more painful, distressing, and disabling than tardive dyskinesia. In th is article, evidence is reviewed on the face, descriptive, construct and pr edictive validity of this iatrogenic complication of antipsychotic drugs. I t is suggested that TDt should not be lumped together with TDk. It deserves a separate nosological status as an independent diagnostic category. The s ubclassification of TDt into various subtypes based on coexistence of other movement disorders is suggested. (C) 1999 Society of Biological Psychiatry .