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

September 16, 2005
August 6, 2008
March 2000
October 2007   (final data collection date for primary outcome measure)
Cocaine use
Same as current
Complete list of historical versions of study NCT00218075 on Archive Site
  • Medication compliance
  • treatment retention
  • severity of addiction-related problems
Medication compliance, treatment retention, and severity of addiction-related problems
Not Provided
Not Provided
Behavioral Therapy Combined With Carbidopa/Levodopa for the Treatment of Cocaine Dependence
Behavioral Strategies to Maximize the Efficacy of Pharmacotherapy for Cocaine Dependence: Relapse Prevention With Contingency Management Procedures

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.

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.

Phase 2
Allocation: Randomized
Endpoint Classification: Safety/Efficacy Study
Intervention Model: Parallel Assignment
Masking: Double-Blind
Primary Purpose: Treatment
  • Cocaine Abuse
  • Cocaine-Related Disorders
  • Drug: Levodopa
  • Drug: Carbidopa
  • Behavioral: Clinical Management
  • Behavioral: Relapse Prevention Therapy
  • Behavioral: Contingency Management
Not Provided
Not Provided

*   Includes publications given by the data provider as well as publications identified by Identifier (NCT Number) in Medline.
October 2007
October 2007   (final data collection date for primary outcome measure)

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
18 Years to 55 Years
Contact information is only displayed when the study is recruiting subjects
United States
NIDA-09262-9, P50-09262-9, DPMC
Not Provided
Not Provided
National Institute on Drug Abuse (NIDA)
University of Texas
Principal Investigator: John Grabowski, PhD University of Texas
National Institute on Drug Abuse (NIDA)
August 2008

ICMJE     Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP