Extrapyramidal effect of neuroleptics.

Studied 66 psychiatric inpatients who had taken major tranquilizers (chlorpromazine, thioridazine, trifluoperazine, fluphenazine, and haloperidol) for periods of 4-16 yrs. The frequency of signs of parkinsonism and the effects of orphenadrine on these were studied in a double-blind crossover method. 40 Ss (61%) showed signs of parkinsonism. Female Ss and those with organic brain pathology more frequently exhibited parkinsonism (although the difference was not statistically significant). No correlation was found between duration of treatment and extrapyramidal effects. Of the 40 Ss who developed parkinsonism, 25 responded favorably to orphenadrine, while 6 had more marked manifestations on orphenadrine than on placebo. (PsycInfo Database Record (c) 2022 APA, all rights reserved)