Behavioral Therapy Combined With Carbidopa/Levodopa for the Treatment of Cocaine Dependence

This study has been completed.
University of Texas
Information provided by:
National Institute on Drug Abuse (NIDA) Identifier:
First received: September 16, 2005
Last updated: August 6, 2008
Last verified: August 2008

Cocaine dependence is a major public health problem; an effective primary treatment for cocaine dependent individuals has yet to be found. The purpose of this study is to examine the effectiveness of levodopa and carbidopa in treating cocaine dependent individuals. In addition, this study will examine the effects of incentive rewards for treatment compliance.

Condition Intervention Phase
Cocaine Abuse
Cocaine-Related Disorders
Drug: Levodopa
Drug: Carbidopa
Behavioral: Clinical Management
Behavioral: Relapse Prevention Therapy
Behavioral: Contingency Management
Phase 2

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Safety/Efficacy Study
Intervention Model: Parallel Assignment
Masking: Double-Blind
Primary Purpose: Treatment
Official Title: Behavioral Strategies to Maximize the Efficacy of Pharmacotherapy for Cocaine Dependence: Relapse Prevention With Contingency Management Procedures

Resource links provided by NLM:

Further study details as provided by National Institute on Drug Abuse (NIDA):

Primary Outcome Measures:
  • Cocaine use

Secondary Outcome Measures:
  • Medication compliance
  • treatment retention
  • severity of addiction-related problems

Estimated Enrollment: 200
Study Start Date: March 2000
Study Completion Date: October 2007
Primary Completion Date: October 2007 (Final data collection date for primary outcome measure)
Detailed Description:

Cocaine is a strong central nervous system stimulant that is widely abused throughout the United States. Due to its widespread use, it is important to develop an effective treatment for cocaine dependence. Levodopa is a medication that is used alone or in combination with carbidopa to treat Parkinson's disease. The purpose of this study is to determine the possible interactions between behavioral interventions and carbidopa/levodopa in order to treat cocaine dependent individuals.

This study will last 12 weeks and will involve two phases. The first phase will include three therapy conditions: 1) clinical management only, 2) clinical management and relapse prevention therapy, and 3) clinical management, relapse prevention therapy, and contingency management. All of the conditions in the first phase will be evaluated incrementally under active and placebo conditions while participants receive carbidopa/levodopa.

The second phase of the study will examine the contingency management procedure applications. Each of the three contingency management procedure applications targets specific behaviors that, when reinforced, may interact with carbidopa/levodopa to produce clinical benefits. Participants will receive relapse prevention therapy combined with a contingency management procedure that targets clinic attendance, medication compliance, and cocaine abstinence. Study visits will occur weekly throughout the study. In addition, participants will complete a one-year follow-up visit.


Ages Eligible for Study:   18 Years to 55 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • Meets DSM-IV criteria for current cocaine dependence
  • Provides at least one positive urine test for cocaine during study screening
  • Good general health, based on a physical exam, lab tests, and an electrocardiogram
  • Reads and writes English at a sixth grade level

Exclusion Criteria:

  • Current Axis I depressive, psychotic, or anxiety disorder
  • Currently in jail
  • Pregnant or breastfeeding
  • Requires certain medications
  Contacts and Locations
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Please refer to this study by its identifier: NCT00218075

United States, Texas
University of Texas Health Science Center
Houston, Texas, United States, 77030
Sponsors and Collaborators
University of Texas
Principal Investigator: John Grabowski, PhD University of Texas
  More Information

No publications provided Identifier: NCT00218075     History of Changes
Other Study ID Numbers: NIDA-09262-9, P50-09262-9, DPMC
Study First Received: September 16, 2005
Last Updated: August 6, 2008
Health Authority: United States: Federal Government

Additional relevant MeSH terms:
Cocaine-Related Disorders
Chemically-Induced Disorders
Mental Disorders
Substance-Related Disorders processed this record on March 25, 2015