Related Experiment Video
Updated: Jun 9, 2026

Protocol for Repetitive Transcranial Magnetic Stimulation with Symptom Provocation to Treat Obsessive-compulsive Disorder
Published on: November 25, 2025
A double-blind, placebo-controlled pilot study of ondansetron for patients with obsessive-compulsive disorder
Farhad Soltani1, Mehdi Sayyah, Fariba Feizy
1Department of Anesthesiology, Jundishapur University of Medical Sciences, Ahwaz, Iran.
Objective:
To assess the efficacy and tolerability of ondansetron in combination with selective serotonin reuptake inhibitors (SSRIs) in patients with obsessive-compulsive disorder (OCD).
Methods:
The study was an 8-week pilot double-blind randomized clinical trial. Forty-two adult outpatients who met the Diagnostic and Statistical Manual, Fourth Edition, Text Revision (DSM-IV-TR) criteria for OCD based on the structured clinical interview participated in the trial. In this study, patients were randomly assigned to receive either ondansetron (4 mg) plus fluoxetine or fluoxetine (20 mg/day) plus placebo.
Results:
The results showed a significant difference between two groups in the treatment of OCD (based on t-test). There was not any significant difference between the two groups in terms of observed side effects.
Conclusions:
The results of this study show that ondansetron has positive effects on obsession and compulsion which start two weeks after the beginning of the treatment.
Related Concept Videos
Obsessive-Compulsive Disorder
Chemotherapy-Induced Nausea and Vomiting: 5-HT3 Receptor Antagonists
Chemotherapy-Induced Nausea and Vomiting: Dopamine Receptor Antagonists
Phenothiazines, such as prochlorperazine...
Drugs for Treatment of Constipation-Predominant IBS
Generalized Anxiety Disorder
Drugs Affecting GI Tract Motility: Serotonin Receptor Agonists

