The role of ondansetron in the treatment of schizophrenia.
Author(s): Bennett AC, Vila TM.
Affiliation(s): PPD, Inc., Morrisville, NC 27560, USA.
Publication date & source: 2010, Ann Pharmacother. , 44(7-8):1301-6
OBJECTIVE: To evaluate the efficacy of ondansetron for the treatment of
DATA SOURCES: Searches of MEDLINE (1950-March 2010) and Google Scholar were
performed. Key search terms included ondansetron, Zofran, serotonin antagonists,
5-HT(3) serotonin receptor, and schizophrenia.
STUDY SELECTION AND DATA EXTRACTION: All articles published in English identified
from the data sources were evaluated. All studies and case reports evaluating
ondansetron for the treatment of schizophrenia were reviewed.
DATA SYNTHESIS: Six clinical trials, including 3 double-blind, randomized trials,
and 2 case reports pertinent to ondansetron use in schizophrenia, were
identified. Ondansetron daily doses ranged from 4 to 16 mg, with doses
administered once or twice daily. Ondansetron was used as monotherapy in 3 trials
and as an adjunct to therapy with clozapine, haloperidol, or risperidone,
respectively, in 3 trials. Studies were of varying durations, ranging from a
single-dose study with a 3-hour follow-up to three 12-week studies. Most studies
evaluated ondansetron's efficacy in treating schizophrenia as measured with
changes in Positive and Negative Syndrome Scale (PANSS), Brief Psychiatric Rating
Scale, and Clinical Global Impression scale scores. In the 2 largest trials, with
a combined patient population of 151, treatment with adjunctive ondansetron
resulted in statistically significant improvement in negative symptoms as
assessed with PANSS. In all studies, ondansetron was well tolerated, with no
severe adverse reactions reported.
CONCLUSIONS: Ondansetron may be effective as an adjunct to antipsychotics for the
treatment of schizophrenia, specifically negative symptoms, as assessed with
PANSS. Due to the variation in concurrent therapies and dosing regimens, it is
difficult to establish an optimal dose from the reviewed trials. Further large,
randomized, double-blind, active-controlled studies would be helpful in
determining the role of ondansetron in the treatment of schizophrenia.