Two cases of risperidone-induced tardive dyskinesia and a review of the literature.

Acase in which a 26 year old patient with undifferentiated schizophrenia, showing abnormal oral, lingual and jaw movements suggestive of tardive dyskinesia during a dose reduction of risperidone, is presented. A second case, relating to a 39 year old married woman diagnosed as having a DSM-IV schizophreniform disorder is also presented. These two cases are discussed in relation to the existing literature.