title: Early onset of antipsychotic response in the treatment of acutely agitated patients with psychotic disorders.
abstract: OBJECTIVE
  While the efficacy of antipsychotic medications for the treatment of psychosis is generally established, the speed of onset of antipsychotic action remains controversial. The objective of this study was to evaluate the early response (within the first 24 h) in psychosis with ziprasidone IM treatment, and to determine whether this early effect is distinct from a reduction in agitation symptoms.
  
  
  METHODS
  In a 24-h, double-blind study, hospitalized patients with psychotic disorder and acute agitation were randomized to treatment with fixed doses of IM ziprasidone: 2 mg (N=38) or 20 mg (N=41). Efficacy assessments were based on the PANSS positive subscale and PANSS early psychosis factor score (conceptual disorganization, hallucinatory behavior, and unusual thought content) at 4 and 24 h.
  
  
  RESULTS
  Ziprasidone IM demonstrated a significant dose-related effect (20 mg vs. 2 mg) on both the PANSS early psychosis factor score and the PANSS positive subscale at the first post-baseline time point (4 h), and at 24 h (all p<0.05). There was a significant direct effect of ziprasidone IM on early psychosis at 24 h (p<0.05), distinct from improvement in agitation symptoms.
  
  
  CONCLUSIONS
  These findings suggest, in addition to an early reduction in acute agitation, ziprasidone IM may be associated with a more rapid improvement in psychotic symptoms than previously reported, thus lending further support to the emergent hypothesis of early psychosis improvement in antipsychotic treatment.
authors.affiliation: Center for Addiction and Mental Health, 250 College St., Toronto, Ontario, Canada M5T 1R8. Ofer_agid@camh.net
authors.forename: Ofer
authors.initials: O
authors.lastname: Agid
authors.forename: Shitij
authors.initials: S
authors.lastname: Kapur
authors.forename: Lewis
authors.initials: L
authors.lastname: Warrington
authors.forename: Antony
authors.initials: A
authors.lastname: Loebel
authors.forename: Cynthia
authors.initials: C
authors.lastname: Siu
mesh_terms: D000208:Acute Disease; D000328:Adult; D014150:Antipsychotic Agents / Q000627:therapeutic use*; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D005260:Female; D006760:Hospitalization; D006801:Humans; D008297:Male; D010879:Piperazines / Q000627:therapeutic use*; D011569:Psychiatric Status Rating Scales / Q000706:statistics & numerical data; D011595:Psychomotor Agitation / Q000175:diagnosis / Q000188:drug therapy* / Q000523:psychology; D011618:Psychotic Disorders / Q000175:diagnosis / Q000188:drug therapy* / Q000523:psychology; D013844:Thiazoles / Q000627:therapeutic use*; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D014150:Antipsychotic Agents; D010879:Piperazines; D013844:Thiazoles; C092292:ziprasidone