Tardive dyskinesia in young mentally retarded individuals.

The results of a systematic neuroleptic withdrawal study in 38 mentally retarded children, adolescents, and young adults are described. The focus of the study was the occurrence of side effects of chronic neuroleptic treatment: tardive dyskinesia, transient withdrawal dyskinesia, nondyskinetic withdrawal symptoms, and a possible behavioral analogue of withdrawal dyskinesia. Transient side effects were noted in 34% of the subjects, and tardive dyskinesia in an equal proportion. The data suggest that cumulative neuroleptic dose may play a role as a risk factor in the development of severe tardive dyskinesia.