Tardive dyskinesia. A discontinuation study.

Twenty-one nonschizophrenic and 12 schizophrenic outpatients with tardive dyskinesia (TD) were followed up for a mean of 12.0 and 8.6 months, respectively, following discontinuation of neuroleptic therapy. Of the 33 patients, only one demonstrated complete reversal of TD. Cumulative survival curves of the length of time to first improvement (reduction in movement ratings by 50% of baseline) did not differ between the two groups. The median time to first improvement was seven months. If a patient can be kept off of a neuroleptic regimen for 18 months, the estimated probability of showing a 50% reduction in movement is 87.2%. In the nonschizophrenic group, depressed mood was negatively correlated with severity of abnormal movements.