Improved p50 auditory gating with ondansetron in medicated schizophrenia patients.
OBJECTIVE
Most schizophrenia patients have a deficit in auditory sensory gating, which appears to be mediated by the alpha-7 nicotinic receptor, that is not improved with conventional antipsychotic treatment. This study examined the effects of ondansetron, a highly selective 5-HT3 antagonist, on the P50 auditory evoked potential.


METHODS
Eight medicated outpatients with schizophrenia were given either ondansetron (16 mg) or placebo in a double-blind, placebo-controlled design. Evoked potentials were recorded at baseline and 1 hour, 2 hours, and 3 hours after receipt of drug.


RESULTS
There was a highly significant improvement in P50 gating after ondansetron treatment. The maximal treatment difference was at 2 hours posttreatment (ondansetron: mean=41.4%, SD=39.7%; placebo: mean=80.2%, SD=21.3%).


CONCLUSIONS
Ondansetron significantly enhanced P50 auditory gating in schizophrenia patients treated with typical antipsychotics.
Adler
Lawrence E
LE
Denver VA Medical Center, 1055 Clermont St., Denver, CO 80220, USA. Lawrence.Adler@med.va.gov
Cawthra
Ellen M
EM
Donovan
Kara A
KA
Harris
Josette G
JG
Nagamoto
Herbert T
HT
Olincy
Ann
A
Waldo
Merilyne C
MC
D000161:Acoustic Stimulation; D000328:Adult; D014150:Antipsychotic Agents / Q000627:therapeutic use*; D018592:Cross-Over Studies; D004311:Double-Blind Method; D004359:Drug Therapy, Combination; D005072:Evoked Potentials, Auditory / Q000187:drug effects*; D005260:Female; D006801:Humans; D008297:Male; D017294:Ondansetron / Q000494:pharmacology* / Q000627:therapeutic use*; D010919:Placebos; D011978:Receptors, Nicotinic / Q000187:drug effects; D012559:Schizophrenia / Q000175:diagnosis / Q000188:drug therapy*; D012702:Serotonin Antagonists / Q000494:pharmacology* / Q000627:therapeutic use*; D016896:Treatment Outcome
D014150:Antipsychotic Agents; D010919:Placebos; D011978:Receptors, Nicotinic; D012702:Serotonin Antagonists; D017294:Ondansetron