Can atypical antipsychotics improve tardive dyskinesia associated with other atypical antipsychotics? Case report and brief review of the literature.

Tardive dyskinesia (TD) is a devastating adverse effect of long-term antipsychotic drug treatment. Atypical antipsychotics produce less TD, and it has been shown that they may have a therapeutic effect on pre-existing TD. Here, we report a case of olanzapine-induced TD which did not improve after switching to risperidone but improved after the addition of quetiapine to risperidone regimen. We also provide a brief review of the reported cases on TD induced by atypical antipsychotics which improved after switching to another atypical agent. It is unclear whether some atypical antipsychotics are more effective than others in the treatment of TD. Differences in this property and the underlying mechanism require further study.