Beta-blockade Effects on Memory for Cocaine Craving

Phase 2

Completed

Conditions: Cocaine Dependence

Interventions: Drug: Placebo
Drug: Propranolol

Registration Number: NCT00830362

Lead Sponsor: Medical University of South Carolina

Brief Summary: The purpose of this study is to examine the effects of propranolol versus placebo on responses to cocaine cues in cocaine dependent individuals.

Detailed Description: This study will employ cocaine-dependent individuals to investigate the acute effects of propranolol vs. placebo, administered immediately after a retrieval session of cocaine cue exposure, on the subjective and physiological responses occurring during a subsequent test session of cocaine cue exposure. Participants (N=52) will be randomly assigned to receive 40 mg propranolol or placebo immediately after the first of two cocaine cue exposure sessions scheduled to occur on consecutive days of an inpatient stay at MUSC's General Clinical Research Center (GCRC). The first session will serve as a retrieval session where cocaine cue exposure will putatively elicit retrieval and reconsolidation of memories about the association between the cues and cocaine administration; the second session of cocaine cue exposure will be a test session to examine the potential modulatory role of propranolol on the reconsolidated memories putatively elicited during the previous cue exposure session. It is assumed that changes in craving and physiological reactivity during the test session will reflect propranolol's effects on memory reconsolidation processes elicited by cue exposure during the retrieval session. Medications will be administered in a double-blind fashion. Craving and physiological arousal (heart rate, skin conductance, blood pressure) will be obtained at baseline and at regular intervals during and after both cue exposure sessions. Approximately 7 days following discharge from the inpatient stay at the GCRC, participants will return to the GCRC to undergo a 1-week follow-up cue exposure session that will be identical to the previous two sessions (no medications will be administered). The goal of the follow-up will be to examine if any craving and/or physiological reactivity differences identified during the test session were sustained and to assess if the groups differed in their cocaine use during the intervening 7-day period.

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 50

Inclusion Criteria

Current cocaine dependence (within past month)
Able to provide informed consent
Use of birth control by female participants (barrier methods, surgical sterilization, IUD, or abstinence)
Live within 50-mile radius of research site
Consent to remain abstinent from all drugs of abuse (except nicotine) for 24 hours prior to inpatient admission and follow-up assessment
Consent to random assignment to propranolol or placebo

Exclusion Criteria

Women who are pregnant, nursing or are of childbearing potential and not practicing/using birth control
Evidence or history of significant hematological, endocrine, cardiovascular, pulmonary, renal, gastrointestinal or neurological disease
Significant liver impairment
History of or current psychotic disorder, current severe major depressive disorder, bipolar affective disorder or a severe anxiety disorder
Currently taking anti-arrhythmic agents, psychostimulants or other agents known to interfere with heart rate and skin conductance monitoring
Known or suspected hypersensitivity to propranolol
Individuals taking medications that could adversely interact with the study medication, including, but not limited to albuterol, insulin, or significant inhibitors of CYP2D6
Individuals with bronchial asthma or chronic obstructive pulmonary disease

Study & Design

Study Type: INTERVENTIONAL

Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Placebo	Placebo	-
Propranolol 40mg	Propranolol	-

Primary Outcome Measures

Name	Time	Method
Single Item Craving Test Session Difference Scores	Both days of cue exposure	Mean of the difference of Session 1 and Session 2 cocaine craving scores (Session 2-Session 1). Found by using our Single Item Craving (SIC) scale. A study team member asks the participant to verbally report the level of craving they were experiencing using values between 0 and 100, with 0 representing no craving and 100 extreme craving. The difference score was found by subtracting session 1 mean SICs during cue exposure from session 2 mean SICs during cue exposure. Therefore the mean of the difference could have ranged anywhere from -100 to 100. Negative mean difference scores reflect a decrease in craving for cocaine from session 1 (test) to session 2 (retrieval). The lower the mean difference score, the greater the decrease in craving.

Secondary Outcome Measures