Clinical trial NCT00240227
Conditions: Alcoholism Cocaine Dependence
Keywords: Alcoholism Cocaine Dependence Prazosin Substance use disorders
Sponsor: US Department of Veterans Affairs
Start date: 2004-04-01; Completion date: 2009-01-01
Enrollment: 8 participants; Allocation: RANDOMIZED; Intervention model: CROSSOVER

Brief summary:
This double-blind placebo controlled crossover pilot trial will test the hypothesis that prazosin, an alpha-1 adrenergic receptor antagonist, reduces craving for their drug of choice in cocaine-dependent and alcohol-dependent veterans. Both the study medication period and the placebo period are each 4 weeks in duration.

Detailed description:
1. Objective of the project: To evaluate the efficacy of prazosin on the reduction of craving in alcohol and cocaine dependent individuals. The investigators hypothesize that prazosin will be more effective than placebo in the reduction of craving that is stimulated by exposure to visual cues or to intolerance to stress in individuals dependent on cocaine and in individuals dependent on alcohol.

   Specifically, the investigators hypothesize that in this laboratory study:
   * Subjects in the prazosin condition will report a reduction in craving induced in the laboratory by exposure to visual cues compared to subjects in the placebo condition.
   * Subjects in the prazosin condition will show less reaction of the noradrenergic system when craving is induced in the laboratory by exposure to visual cues compared to subjects in the placebo condition.
   * Subjects will be less likely to relapse to their drug of choice while they are in the prazosin condition compared to when they are in the placebo condition. Most individuals who are able to achieve sobriety in chemical dependency treatment eventually relapse. Until the investigators can prevent the cravings for drugs, which usually precedes relapse, it is unlikely that the investigators will have more effective treatment for drug addiction. Our final hypothesis is that the alpha-1, adrenergic antagonist, prazosin, will prove to be an effective pharmacological agent for treatment of drug dependency.
2. Research plan study design: The proposed study will be a double-blind, placebo-controlled, crossover study of prazosin in subjects who are either dependent on alcohol or on cocaine, and who have been able to achieve one month of sobriety while in intensive outpatient treatment. The double-blind, crossover protocol will last 8 weeks and will include 32 subjects; 16 of whom are alcohol-dependent, and 16 of whom are cocaine-dependent. The focus of this first study will be on subjective and physiological measures of craving that will be induced in a controlled setting by exposure to visual cues.
3. Methodology Setting: This study will occur in room 6A-107 in Building 1 at the Veterans Administration Puget Sound Health Care System in Seattle. This is a soundproof room specifically designed and constructed for studies of this type. Participants: 16 alcohol-dependent adults and 16 cocaine-dependent adults presenting for chemical dependency treatment at the VA Puget Sound Health Care System (VAPSHCS) Addiction Treatment Center. Study Procedures: Once potential subjects have provided their consent to participate in the study, they will undergo a 2 hour baseline assessment that consists of some pencil and paper questionnaires, providing a medical and psychiatric history, and a physical exam. They will provide blood for some basic screening labs to insure they are healthy enough to proceed with the study, and have their baseline vital signs measured. Veterans who are screened for the study will then be enrolled once their lab results and the screening process have determined that they do not meet any medical exclusion criteria. At that point, participants will be randomized to either the study medication or placebo. During the course of the study, participants continue with their outpatient chemical dependency treatment through the Addiction Treatment Center at the VA Puget Sound. During the eight weeks of the study, participants will have weekly orthostatic vital sign and adverse events monitoring by the study nurse or physician. All serious or unexpected adverse events will be reported to the FDA and UW Human Subjects Committee in accordance with requirements. Participants will also provide self-reports of drug or alcohol use and urine drug analysis specimens at these weekly visits. At the end of week 4, each participant will be tested in a 1 hour craving session in room 6A-107 at VA Puget Sound. Subjects will have their heart rate and skin conductance response continuously measured, and have their blood pressure measured every 5 minutes. They will be shown 5 1-minute films, 3 of which are designed to be neutral and 2 of which are designed to provoke craving for their drug of choice. They will be asked to complete a subjective scale of craving prior to each video and after the last video. Participants will not be permitted to leave the craving lab after the last film, until they feel that they have subjectively returned to a level of normal physiological arousal and are no longer experiencing any craving.
4. Findings: No findings to date.

Arms: arm 1: Placebo no active medication arm 2: Prazosin flexible dose titration up to 12 mg per day.
Interventions: intervention 1: Prazosin intervention 2: placebo
Intervention descriptions: intervention 1: FDA approved medication for hypertension intervention 2: None

Protocol documents: