Related Experiment Video
Updated: May 10, 2026

Three Laboratory Procedures for Assessing Different Manifestations of Impulsivity in Rats
Published on: March 17, 2019
Olanzapine versus haloperidol: which can control stuttering better?
Vahid Shaygannejad1, Seyed Ahmadreza Khatoonabadi, Bijan Shafiei
1Department of Neurology, Isfahan Neurosciences Research Center, Isfahan University of Medical Sciences, Isfahan, Iran.
Olanzapine demonstrated a superior effect in managing stuttering symptoms compared to haloperidol. This study suggests olanzapine may be a preferred first-line treatment for stuttering, requiring careful patient monitoring.
Area of Science:
- Pharmacology
- Speech-Language Pathology
- Clinical Trials
Background:
- Stuttering, a complex speech disorder, presents significant challenges in management.
- Antipsychotic medications are sometimes explored for their potential to modulate speech patterns.
Purpose of the Study:
- To compare the efficacy of olanzapine and haloperidol in controlling stuttering.
- To evaluate the impact of these medications on stuttering severity.
Main Methods:
- A 12-week single-blind randomized clinical trial involving 93 patients.
- Patients received either olanzapine (5 mg/day) or haloperidol (2.5 mg/day).
- Speech pathologists assessed stuttering using Van Riper's questionnaire before and after treatment.
Main Results:
- Both groups showed reduced stuttering scores post-treatment.
- The olanzapine group exhibited a significantly greater reduction in stuttering scores (P = 0.000).
- Initial stuttering scores were comparable between the haloperidol and olanzapine groups (P > 0.05).
Conclusions:
- Olanzapine appears to be more effective than haloperidol in controlling stuttering.
- Olanzapine may be considered a potential first-choice medication for stuttering management.
- Careful follow-up is recommended when prescribing olanzapine for stuttering.
Related Concept Videos
Psychosis: Goals of Pharmacotherapy
Antipsychotic Drugs: Typical and Atypical Agents
Drug Therapy
Antianxiety Medications
Psychosis and Antipsychotic Drugs: Overview
Antipsychotic Drugs: Therapeutic Uses and Side Effects
Despite these side effects, antipsychotics are used therapeutically for various purposes, including managing schizophrenia, preventing nausea and vomiting, curbing...
Mania and Antimanic Drugs: Overview