With the introduction of atypical neuroleptic medications into the market place, usage of conventional neuroleptics has fallen with the perception of a more favorable atypical side effect profile. Although there is some evidence that atypical neuroleptics are associated with a decreased occurrence of tardive dyskinesia (TD), reports of atypical-induced TD are appearing in the literature. OBJECTIVE: The purpose of this study was to determine the risk of TD associated with atypical and conventional neuroleptics. METHODS: Subjects were adult users of the Veterans Administration Puget Sound Health Care System who received ? 1 prescriptions for neuroleptic medications during the study period. Electronic medical and pharmacy records were used to obtain neuroleptic drug exposure, exclusionary diagnosis, diagnosis for TD, and select demographic data. Medical records were reviewed to collect demographic data not available electronically. The case-defining event was the diagnosis of TD. Controls were randomly selected from a cohort of neuroleptic users without TD. RESULTS: There were 48 cases and 179 controls for the final analysis. The only demographic difference found was a higher proportion of cases (92%) than controls (76%) were Caucasian. Conventional neuroleptic users had an insignificant increase in risk of TD over atypical neuroleptic users (OR = 1.16; 95%CI = 0.607 2.21). After adjusting for age, gender, race, schizophrenia, schizo-affective disorder, depression, and antiparkinson drugs, there was still no significant difference in risk of TD between cases and controls (OR = 1.46; 95% CI = 0.625 3.414). CONCLUSIONS: These results suggest users of conventional neuroleptics may be at increased risk of TD compared to users of atypical neuroleptics, however in this population the increase was not significant.