Treatment of Clozapine-Induced Hypersalivation Ipratropium Bromide


Hypersalivation (Too much saliva) and drooling is a side effect experienced by 31% of people taking the antipsychotic clozapine. This study aims to determine if using the medication ipratropium bromide(IPB)at bedtime will reduce the amount of salivation and the distress people may feel.

Study Type

  • Study Type: Interventional
  • Study Design
    • Allocation: Randomized
    • Intervention Model: Crossover Assignment
    • Primary Purpose: Treatment
    • Masking: Double (Participant, Investigator)
  • Study Primary Completion Date: June 2008

Detailed Description

With the recent questions regarding the effectiveness of newer atypical antipsychotic medications in treating schizophrenia, clozapine continues to remain the gold standard for treatment-refractory schizophrenia. However, treatment with clozapine continues to be limited by its many side effects. The second most common side effect, occurring in 31% of clozapine treated patients, is hypersalivation or sialorrhea. Sialorrhea can be profoundly stigmatizing and functionally disabling in certain patients, and may increase discontinuation rates in this high-risk patient population. Several studies have evaluated the efficacy of anticholinergic agents mainly in small, uncontrolled studies or anecdotal reports and are often complicated by difficulties in medication administration and systemic side effects. Open label and case series studies have demonstrated promising results with ipratropium bromide (IPB) treatment of clozapine-induced hypersalivation, acting on anticholinergic receptors with minimal systemic absorption. However, no randomized controlled trials have evaluated IPB in the treatment of this problematic side effect.The primary goals of this study is to determine the efficacy of ipratropium bromide in reducing clozapine-induced hypersalivation, as per the Toronto Nocturnal Hypersalivation Scale, which is a modified hypersalivation scale incorporating the Drooling Severity Scale and the Nocturnal Hypersalivation Rating Scale, and reduced measurements on visual analogue scales for hypersalivation distress and severity. Our hypothesis that Ipratropium bromide use at bedtime will result in a significant reduction in nocturnal clozapine-induced hypersalivation as measured by the Toronto Nocturnal Hypersalivation Scale (TNHS) through its local anticholinergic activity.


  • Drug: ipratropium bromide 0.03% spray

Arms, Groups and Cohorts

  • Experimental: A
    • Random assignment to investigational spray

Clinical Trial Outcome Measures

Primary Measures

  • Toronto Nocturnal Hypersalivation Scale scores
    • Time Frame: intermittent
  • Visual Analogue Scale – Severity
    • Time Frame: intermittent
  • Visual Analogue Scale – Distress
    • Time Frame: Intermittent
  • Simpson-Angus Rating Scale
    • Time Frame: Each study visit
  • Clinical Global Improvement Scale
    • Time Frame: Each study visit

Participating in This Clinical Trial

Inclusion Criteria

  • Diagnosis of schizophrenia or schizoaffective disorder as per DSM IV-TR criteria
  • Receiving clozapine for at least 2 months
  • No change in their clozapine dose for at least 2 weeks
  • Have a Clinical Global Impression scale score for hypersalivation of greater than or equal to 4
  • Have the capacity to provide voluntary, informed consent
  • Able to speak English
  • Have a minimum score of 2 on the TNHS prior to study entry
  • No change in medications for at least 2 weeks

Exclusion Criteria

  • Subjects with co-morbid medical conditions that could influence hypersalivation (e.g. Idiopathic Parkinson's Disease)
  • Subjects currently receiving ipratropium bromide for the treatment of hypersalivation or other medical conditions
  • History of narrow-angle glaucoma, prostatic hyperplasia or bladder neck obstruction
  • History of an allergic reaction to ipratropium bromide

Gender Eligibility: All

Minimum Age: 18 Years

Maximum Age: N/A

Are Healthy Volunteers Accepted: No

Investigator Details

  • Lead Sponsor
    • Centre for Addiction and Mental Health
  • Provider of Information About this Clinical Study
    • Dr. Gary Remington, Centre for Addiction and Mental Health
  • Overall Official(s)
    • Gary Remington, MD, PhD, Principal Investigator, Centre for Addiction and Mental Health

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