This article presents data from two avenues of marijuana research. First, the author shows that daily marijuana smoking in healthy individuals produces dependence, as demonstrated by withdrawal symptoms such as increased irritability and depression and decreased food intake. In addition, two antidepressant medications were evaluated to assess their potential effectiveness in the treatment of marijuana withdrawal symptoms: (1) sustained-release bupropion (0, 300 mg/day) and (2) nefazodone (0, 450 mg/day). Research participants were regular marijuana smokers who lived in a residential laboratory in groups of two to four. While inpatients, participants smoked active marijuana (2.8%-3.1% THC) repeatedly for 4 days, followed by 8 to 12 days of placebo marijuana (0.0% THC). Results show that during marijuana abstinence, (1) bupropion increased ratings of irritability, depression, and stomach pain and decreased food intake and sleep quality compared to placebo maintenance, and (2) nefazodone decreased anxiety during marijuana withdrawal but did not alter ratings of irritability and misery. Thus, neither medication showed promise as potential treatments for symptoms of marijuana withdrawal. The second avenue of research focused on the effect of cannabinoids in individuals with muscle mass loss, an indicator of wasting in HIV illness. Given that there are little scientific data contributing to the debates concerning medical marijuana, this study directly compared the effects of oral delta9-THC (0, 10, 20, 30 mg PO) to smoked marijuana (0.0%, 1.8%, 2.8%, 3.9% THC) in HIV + marijuana smokers with muscle mass loss (< 90% body cell mass/height). Multiple dimensions of human behavior were measured, including food intake, mood, and cognitive performance. Drugs were administered using a within-subject, double-blind, staggered, double-dummy design. Participants were free to self-select from a variety of foods throughout most of the session. Preliminary data (n = 9) suggest that oral THC was more effective at increasing food intake, but the volunteers "liked" the effects of smoked marijuana more than the effects of oral THC.