This study is being done to better understand cannabis withdrawal and to test whether a new medication can help reduce the symptoms people experience when they stop using cannabis.

You may be eligible for this study if you meet the following criteria.

Inclusion Criteria:

• Adults ages 18–55
• Use cannabis daily or most days for the past 6 months
• Strongly motivated to stop cannabis use
• Willing to spend 7 days in‑patient as part of the research study

Exclusion Criteria:

• Current unstable or major psychiatric disorder or medical condition
• Currently pregnant or breastfeeding
• Substance use disorder within the prior 6 months other than cannabis, nicotine, or caffeine

The study lasts about 7 weeks. This includes a screening visit, a 7‑day inpatient stay, a 4‑week outpatient treatment period, and two follow‑up check‑ins after treatment ends.

If you join the study, you will come to the research center for several visits. During these visits, you will:

• Complete interviews and questionnaires about your health, mood, and cannabis use

• Take part in simple computer tasks that measure attention and memory

• Provide samples such as blood or urine so researchers can check your health and medication levels

• Stay 7 days in an inpatient research unit, where staff will monitor your withdrawal symptoms and overall well‑being

• Receive either the study medication or a placebo (a pill with no active drug)

• Be monitored daily by medical staff, including vital signs, safety checks, and symptom ratings

• Have some sessions that may be audio‑ or video‑recorded for research purposes (not for public use)

Additional Notes

• All study procedures are free.

• Transportation support may be available for in‑person visits.

• Medical staff are available at all times during the inpatient stay to ensure your safety and comfort.

Participants may receive up to $3,390 in compensation for their time. Transportation support will be available for the study visits.

There is no cost for you to participate in our research study.