Withdrawal-emergent dyskinesia in patients with schizophrenia during antipsychotic discontinuation.

We examined whether patients exhibiting withdrawal-emergent dyskinesia (WE-D) represent a group vulnerable to subsequent development of tardive dyskinesia (TD). WE-D was defined as moderate abnormal movements during antipsychotic withdrawal in persons without persistent TD. We assessed patients with schizophrenia-spectrum illness participating in withdrawal from antipsychotic medication. Patients with WE-D were compared to those without dyskinesia and to those with persistent TD. Clinical measures included duration of illness and antipsychotic exposure, negative symptoms, and neurologic soft signs. We hypothesized that WE-D patients would not differ from persistent-TD patients across the above variables, but would differ from non-TD patients. Patients without TD significantly differed from persistent TD in duration of illness, medication exposure and neurologic soft signs. WE-D did not differ from TD across these measures. No-TD patients also showed less duration of medication exposure and neurologic soft signs than those with WE-D.