Tardive dyskinesia associated with metoclopramide in persons with developmental disabilities

Metoclopramide is an anti-emetic medication that has been associated with movement disorders such as extra-pyramidal reactions and tardive dyskinesia (TD). Reports of these reactions have been documented in the general population, but investigations of side effects in persons with mental retardation are scant. Given the high incidence of gastrointestinal disturbance in persons with mental retardation, and the popularity of this medication to treat such problems, these individuals could be at risk for developing movement disorders resulting from metoclopramide use. We compared incidence rates of TD over a 1-year period in developmentally disabled individuals taking either metoclopramide, typical antipsychotics, or no psychotropic medications (Table 1). Assessment was completed using the Dyskinesia Identification System--Condensed User Scale (DISCUS), a standardized measure of TD found to be reliable and valid for persons with mental retardation. No significant differences in DISCUS scores between the metoclopramide and antipsychotic treated groups were noted across four measurements taken during the course of 1 year. Additionally, no difference was found between these two groups for a number of participants who met criteria for probable TD on at least one of the DISCUS administrations. Comparisons between all three groups on one testing occasion revealed a significant difference between groups. The no psychotropic control group showed significantly less TD symptomology than the antipsychotic or metoclopramide groups.