Drug-induced and other orofacial-cervical dyskinesias.

Tardive dyskinesia is one of the most prevalent and disabling of the iatrogenic disorders. Characterized by involuntary movements of the orofacial-cervical musculature that develop after prolonged use of neuroleptic drugs, it is sometimes confused with other involuntary movements involving predominantly the head and neck region. In this review the differential diagnosis of the orofacial-cervical dyskinesias is discussed. A therapeutic approach is presented in view of our recent understanding of the possible biochemical mechanisms of tardive dyskinesia.