Cannabis use disorders are an important public health problem in the United States, but no effective pharmacotherapies are available to treat these disorders. The investigators intend to test a novel agonist pharmacotherapy, nabilone, for cannabis dependence and to study the relationship of this treatment with the brain using BOLD fMRI measures. The behavioral and physiological effects of nabilone and Δ9-THC overlap, suggesting that nabilone may ameliorate cannabis withdrawal symptoms while allowing treatment-seeking outpatients to benefit from medical management (MM) sessions when they are trying to stop using cannabis. The investigators propose to assess the relationship of nabilone, when added to MM, on cannabis use patterns in cannabis-dependent patients. The investigators also aim to determine the effects of nabilone on performance on neuropsychological tests and to assess the correlation of neuropsychological performance to brain changes using BOLD fMRI measures.~In this pilot study, subjects will receive either nabilone or placebo in addition to medical management (MM) over a 10-week treatment period. Subjects' responses to neuropsychological testing carried out while the subject is receiving fMRI scans at 3 time points: at baseline, 4 weeks, and 10 weeks. Following treatment completion, subjects will have a follow-up visit at 14 weeks. This pilot study will evaluate the feasibility of nabilone treatment for cannabis dependence and will establish effect sizes for a larger trial in which subjects will receive high-dose nabilone, low-dose nabilone, or placebo in addition to MM.
Cannabis use disorders are an important public health problem in the United States, but there are no effective medications available to treat these disorders. The investigators intend to test a medication with interesting properties, nabilone, as a treatment for cannabis dependence and to study the relationship of this treatment with the brain using functional MRI brain scans. Nabilone and marijuana have similar effects upon behaviors and the human body, suggesting that nabilone may decrease cannabis withdrawal symptoms while allowing treatment-seeking patients to benefit from behavioral treatments when they are trying to stop using cannabis. The investigators propose to assess the relationship of nabilone, when added to behavioral treatment, on cannabis use patterns in cannabis-dependent patients. The investigators also aim to determine the effects of nabilone on performance on neuropsychological tests and to assess the correlation of neuropsychological performance to brain changes using functional MRI brain scans. The investigators hypothesize that patients receiving nabilone will reduce their use of cannabis more than patients receiving placebo during this 10-week treatment trial.