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Minimizing Doses of Antipsychotic Medication in Older Patients With Schizophrenia.

NCT00716755 · Status: COMPLETED · Phase: NA · Type: INTERVENTIONAL · Enrollment: 45

Last updated 2022-06-06

No results posted yet for this study

Summary

Since side effects of antipsychotics, dopamine D2 receptor blockers, frequently occur in older patients with schizophrenia and the risk is dose dependent, clinical guidelines universally advocate the use of lower doses. However, there is no report to test this dosing guideline with measurements of D2 receptor blockade caused by antipsychotics. In this study, dopamine D2 receptor occupancy will be measured, using Positron Emission Tomography (PET), in 40 patients aged 50 and older with schizophrenia-spectrum disorders before and after a gradual 40 % dose reduction of antipsychotics that was safely achieved in the past study while setting a target dose still above the lower limit of the dose range recommended in clinical guidelines for older patients. Our goal is to relate changes in clinical outcome, including subjective and objective clinical ratings, to dopamine D2 receptor occupancy, and compare these results with the data for younger patients in the literature.

Conditions

  • Schizophrenia
  • Schizoaffective Disorder
  • Schizophreniform Disorder
  • Delusional Disorder
  • Psychotic Disorder

Interventions

DRUG

Risperidone/Olanzapine and PET scans

Current risperidone/olanzapine users who are 50 or older will be recruited. Dopamine D2 dopamine receptors using a selective D2 dopamine receptor ligand, \[11C\]-raclopride, and plasma levels of risperidone and 9-OH-risperidone, or of olanzapine, and prolactin will be measured on the 1st PET visit. Subsequently, there will be gradual dose reductions of risperidone or olanzapine by 0.5 and 2.5 mg per week, respectively (as long as the total reduction does not exceed 40%). At least 5 days after the termination of the dose taper, participants will have the second PET scan. Participants will be followed up for 24 weeks after the termination of the dose reduction.

Sponsors & Collaborators

  • Centre for Addiction and Mental Health

    lead OTHER

Principal Investigators

  • David C. Mamo, MD MSc · Centre for Addiction and Mental Health

  • Ariel Graff-Guerrero, MD,PhD · Centre for Addiction and Mental Health

Study Design

Allocation
NA
Purpose
TREATMENT
Masking
NONE
Model
SINGLE_GROUP

Eligibility

Min Age
50 Years
Sex
ALL
Healthy Volunteers
No

Timeline & Regulatory

Start
2009-10-31
Primary Completion
2015-08-31
Completion
2015-08-31

Countries

  • Canada

Study Locations

More Related Trials

Entities

Diseases

Read the full study record

This page highlights key information. For complete eligibility criteria, study locations, investigator contacts, and the full protocol, visit the original record on ClinicalTrials.gov.

View NCT00716755 on ClinicalTrials.gov