Tardive dyskinesia and depressive illness

Tardive dyskinesia has been regarded as a long-term complication of neuroleptic administration to patients with the diagnosis of schizophrenia. However, nine of the first fourteen patients evaluated for an investigation of tardive dyskinesia met diagnostic criteria for depression. Neuroleptics produce blockade of post-synaptic dopaminergic receptors. Tardive dyskinesia occurs when neuroleptics are discontinued, and is regarded as a manifestation of super-sensitive post-synaptic dopaminergic receptors. Chronically decreased neurotransmission in the synapse of a patient with depression may contribute to the development of a super-sensitive receptor and could explain the high proportion of patients with depression seen in this sample of patients with tardive dyskinesia.