title: Ondansetron treatment in Tourette's disorder: a 3-week, randomized, double-blind, placebo-controlled study.
abstract: OBJECTIVE
  The aim of the present study was to evaluate the efficacy of ondansetron, a selective 5-HT(3) antagonist, in the treatment of Tourette's disorder.
  
  
  METHODS
  Participants (N = 30) aged 12 to 46 years, diagnosed with DSM-IV Tourette's disorder and resistant to previous haloperidol treatment, were enrolled in a 3-week, randomized, double-blind, placebo-controlled outpatient study. Assessments were conducted at baseline and once a week during the study period. Scales used included the Tourette's Syndrome Global Scale (TSGS), the Yale Global Tic Severity Scale (YGTSS), and the Yale-Brown Obsessive Compulsive Scale. Ondansetron dose was 8, 16, and 24 mg/day in the first, second, and third weeks, respectively.
  
  
  RESULTS
  A significant positive effect of ondansetron on tic severity, as assessed by the TSGS, was noted (baseline vs. endpoint: mean +/-SD = 29.62 +/-20.33 vs. 20.58 +/-12.82, p = .002 vs. placebo). However, no significant effect was detected upon assessing ondansetron/ placebo effect on tic severity with the YGTSS (baseline vs. endpoint: mean +/-SD = 24.04 +/-9.44 vs. 17.50 +/-9.48, p = .15 vs. placebo). No change in obsessive-compulsive symptoms was noted in either group. Adverse effects included mild and transient abdominal pain.
  
  
  CONCLUSIONS
  Ondansetron may have antitic effects in patients with Tourette's disorder. Large-scale, double-blind studies should further assess the antitic efficacy of ondansetron.
authors.affiliation: Tel-Aviv-Brull Community Mental Health Center, Tel-Aviv, Israel.
authors.forename: Paz
authors.initials: P
authors.lastname: Toren
authors.forename: Abraham
authors.initials: A
authors.lastname: Weizman
authors.forename: Sharon
authors.initials: S
authors.lastname: Ratner
authors.forename: Donald
authors.initials: D
authors.lastname: Cohen
authors.forename: Nathaniel
authors.initials: N
authors.lastname: Laor
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017294:Ondansetron / Q000627:therapeutic use*; D010919:Placebos; D011569:Psychiatric Status Rating Scales; D012702:Serotonin Antagonists / Q000627:therapeutic use*; D012720:Severity of Illness Index; D005879:Tourette Syndrome / Q000175:diagnosis / Q000188:drug therapy* / Q000523:psychology; D016896:Treatment Outcome
chemical_list: D010919:Placebos; D012702:Serotonin Antagonists; D017294:Ondansetron