Effects of Propranolol on Responses to Drug-Related Imagery Scripts

Background:

• Relapse to drug abuse is thought to result, in many cases, from exposure to cues that trigger drug-related memories or emotional associations for example, the association between the sight of a crack pipe and a set of responses such as rapid heartbeat and desire for cocaine. This type of memory is reconsolidated (actively re-stored) each time it is reactivated; however, the reconsolidation process can be disrupted by the drug propranolol, which weakens the link between that memory and an emotional response.
• Propranolol is traditionally used to treat high blood pressure and other heart-related conditions. Researchers are interested in studying whether propranolol disrupts reconsolidation of drug-cued memories in individuals who are addicted to cocaine.

Objectives:

• To examine whether propranolol can interfere with reconsolidation of cocaine-related memories and reduce cravings and drug use in substance abusers.

Eligibility:

• Individuals between 18 and 55 years of age who are current cocaine users enrolled in a methadone treatment program.

Design:

• The study will involve four long sessions (visits 1, 4, 6, and 14) and 10 short sessions. The short visits will be for monitoring of participants use of drugs and alcohol; the longer visits will involve more tests and lab sessions. Participants will be randomized to either the propranolol or placebo group.
• The long sessions will involve the following procedures:
• An interview session to develop a personalized drug script/cue set.
• A two-hour intervention session with baseline measures, drug administration (propranolol or placebo), and two script-guided imagery sets. This is the only administration of propranolol during the study.
• Two follow-up test sessions, 1 and 5 weeks after the intervention session.
• Participants will make brief visits to our outpatient clinic for twice-weekly monitoring of ongoing drug use via urine screens and self-report, starting 1 week before the intervention session and ending 5 weeks later.