After initial eligibility screening, Veterans who use both cannabis and tobacco will be randomly assigned to receive either varenicline (Chantix) or placebo for 12 weeks. Participants will attend weekly visits to provide breath and urine samples for testing, fill out questionnaires, and meet with study staff about medication compliance.

Adults (ages 18+) who would like to reduce their cannabis use (N=224) will be enrolled in an 8-week treatment program. All participants will receive counseling (1 goals session with a therapist followed by 7 weekly computerized cognitive-behavioral therapy sessions). Detailed cannabis assessments (biological and self-report) will be conducted throughout treatment and at 1-, 2-, and 3-months post-treatment completion. Daily electronic diaries will be administered via text message to record detailed logs of cannabis use quantity and frequency. Salivary samples will be collected (and video observed) daily throughout treatment to analyze for progesterone.

Marijuana is the most commonly used illicit drug. There is high demand for effective interventions for cannabis use disorder, yet few specific treatments for have been developed. This study will evaluate the efficacy of varenicline for reducing marijuana use in people who use marijuana frequently.

The purpose of this study is to determine if repetitive transcranial magnetic stimulation (rTMS) reduces opiate craving and pain in Veterans who are receiving treatment for opioid use disorder. The study will last approximately three months. There will be a screening visit to determine eligibility, followed by the treatment phase during which participants will receive six sessions of rTMS a day for three non-consecutive days. This period may take up to three weeks. There are follow up visits at one week, four weeks and three months after the treatment phase has ended.
During rTMS, focused magnetic waves are directed at a part of the brain that is important in pain, and craving, to increase its activity. If you participate, you will receive six sessions of either active rTMS, or placebo rTMS, each day for three days (18 total sessions). Each session lasts 15 minutes. People typically do not have side effects with rTMS, though they initially may find it mildly painful at the application site. About 1 out of every 20 people who get rTMS have mild headaches after sessions that are typically relieved with over-the-counter medicines. A few people who have had rTMS have had seizures, though the chance of this happening is very small.

The purpose of the study is to determine if the hormone progesterone affects marijuana users' stress response and marijuana use. Participation lasts approximately three weeks. During the first week, participants are randomly assigned to take either progesterone or placebo and remain abstinent from marijuana. They return at the end of the week to participate in a stress task. Throughout the three weeks, participants complete "CREMA" sessions (Cue Reactivity Ecologic Momentary Assessment) three times a day. These sessions include looking at stressful and neutral pictures and rating stress and craving.

This study will examine whether the investigational medication PF-0447845 is safe and effective in reducing cannabis use among people who frequently use cannabis. This is a 14-week, randomized, double-blind, placebo-controlled outpatient clinical trial that will be conducted at 4 research sites in the eastern U.S.