Effects of Cannabidiol on Marijuana-seeking in Humans

Participants will be asked to participate in a total of three choice sessions over two weeks with each session day separated by at least two days. Each session day will last approximately 8 hours. During each study session participants will be asked to smoke a cigarette. Participants will be asked to smoke from a marijuana cigarette. These cigarettes may contain cannabidiol or they may not (placebo). Participants will be asked to answer questions about how the drugs make them feel. Vitals signs (blood pressure, heart rate, and oxygen saturation) will be measured using a non-invasive (external) vitals monitor. Six samples will be taken in each of the three sessions. Blood samples will be obtained via butterfly catheter placed in a vein. Participants will be asked to remain in the laboratory until all marijuana-related subjective and physiological effects have returned to the original levels recorded this morning before they smoked the first marijuana cigarette.