title: Reduced haloperidol plasma concentration and clinical response in acute exacerbations of schizophrenia.
abstract: Twenty-nine hospitalized patients suffering acute exacerbations of schizophrenia were treated for 2 weeks with fixed daily oral doses of haloperidol prospectively calculated to achieve a haloperidol plasma concentration of either 8-18 ng/ml or 25-35 ng/ml. Reduced haloperidol as well as haloperidol concentrations were assayed to determine if the former enhanced the predictability of response. Wee 2 haloperidol plasma concentrations were negatively correlated to clinical response as measured by the percentage change in the BPRS score from baseline (r = -0.43, P less than 0.05). In contrast, week 2 plasma concentrations of reduced haloperidol, total haloperidol (haloperidol + reduced haloperidol), and reduced haloperidol/haloperidol ratio did not correlate with the change in the BPRS score. Chi-square analysis concluded that patients with ratios greater than one were no less likely to be treatment responders (less than 25% improvement in BPRS from baseline and week 2 BPRS less than 55) than those with ratios less than one. Although these data lend additional support to reports of a curvilinear relationship between haloperidol plasma concentration and clinical response, they also suggest that reduced haloperidol plasma concentrations are of no value in predicting treatment response.
authors.affiliation: Department of Psychiatry, College of Medicine, University of Iowa, Iowa City 52242.
authors.forename: M W
authors.initials: MW
authors.lastname: Kelly
authors.forename: P J
authors.initials: PJ
authors.lastname: Perry
authors.forename: W H
authors.initials: WH
authors.lastname: Coryell
authors.forename: D D
authors.initials: DD
authors.lastname: Miller
authors.forename: S V
authors.initials: SV
authors.lastname: Arndt
mesh_terms: D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D004305:Dose-Response Relationship, Drug; D005260:Female; D006220:Haloperidol / Q000008:administration & dosage / Q000097:blood* / Q000627:therapeutic use; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012559:Schizophrenia / Q000097:blood / Q000188:drug therapy*
chemical_list: D006220:Haloperidol