The lifetime medication data were considered valid for 133 (80.1%) of the patients. The characteristics of the 133 patients were as follows: male, 73.4% (N=98); diagnosis of schizophrenia, 84.2% (N=112); diabetes mellitus, 11.3% (N=15); leukotomy, 12.8% (N=17); mean age=51.5 years (SD=15.3) (men: mean age=49.4 years, SD=14.2; women: mean age=57.3 years, SD=16.8). The medications used at the time of the assessment consisted of anticholinergics (34.6%, N=46), benzodiazepines (18.0%, N=24), antidepressants (4.5%, N=6), lithium (10.5%, N=14), and others (21.8%, N=29). The current mean neuroleptic dose was 717 mg of chlorpromazine equivalents (SD=748) (men: mean dose=724, SD=700; women: mean dose=700, SD=879). The prevalence of tardive dyskinesia was 36.1% (N=48). T1 shows the relationship between the three lifetime medication variables and the occurrence of tardive dyskinesia. Only the number of neuroleptic interruptions was significantly related to the occurrence of tardive dyskinesia. When the number of neuroleptic interruptions was dichotomized, into two or fewer and more than two, the resulting adjusted odds ratio was 3.29. The linear regression analysis, which determined the relation of each of the three lifetime medication variables to the severity of tardive dyskinesia, showed no significant effect for the lifetime intake of neuroleptics (β=–0.17, t=–1.29, df=120, p=0.20) or the lifetime intake of anticholinergics (β=–0.03, t=–1.91, df=120, p=0.06) but did show a significant effect for the number of neuroleptic interruptions (β=0.36, t=2.43, df=120, p=0.02).