Baclofen Effects on Marijuana Dependence

Studies show that certain reminders of drug use such as the sight of someone using marijuana, pictures of blunts, particular moments throughout the day, prompt marijuana users to smoke marijuana. We are measuring the brain and behavioral responses of marijuana dependent individuals to these reminders (cues) We will examine brain responses during cue exposure and determine whether these responses are associated with treatment outcome. We are testing the hypothesis that the medication baclofen reduces brain responses during marijuana cue exposure and/or craving in marijuana dependent individuals. Baclofen is FDA-approved for other uses, but not for the treatment of marijuana dependence. Functional magnetic resonance imaging (fMRI) will be used to measure the brain's response to marijuana cues. fMRI is a painless technique that takes special pictures of the brain (or other parts of your body). It does not involve radiation or injections. Eligible participants will have a 50% chance of receiving placebo (sugar pill) and a 50% chance of receiving baclofen. Neither the participant nor study personnel will know whether participants are receiving baclofen or placebo. Participants will also receive twice weekly psychosocial treatment with a certified clinician. Twelve weeks of treatment will be followed by a 12 week follow up.