Cannabis Use

The purpose of this study is to identify and evaluate oral fluid testing as a biologic measure of cannabis use days that can be assessed remotely. The researchers will conduct this fully virtual study among a community sample of 200 individuals aged 18-30 years who have used cannabis at least 1 time per week on average in the past 30 days. Participants will complete oral fluid (saliva) tests, urine tests, and Timeline Follow-back interviews (self-report) that indicate their recent cannabis use (delta-9-THC). Participants will present for 3 virtual study visits across \~3-4 weeks and be asked to complete activities in between: Study Visit 1 (Day 0; informed consent, baseline survey, TLFB interview), Study Visit 2 (\~Day 7; TLFB interview, urine testing), 6 days of at-home videorecorded oral fluid testing, Study Visit 3 (\~Day 21; TLFB interview, urine test, oral fluid test, survey, interview).

This inpatient study enrolls healthy individuals who have opioid use disorder. Participants live at the University of Kentucky Hospital for approx. 6 weeks. During this time, we will examine how repeated doses of oral cannabis and acute doses of oral and inhaled cannabis 1) modify the intensity and time course of opioid withdrawal, 2) modify the effects of intranasal opioid administration and 3) impact the safety of opioid administration.

The study will enroll participants with opioid use disorder and participants will reside at the University of Kentucky Hospital for this 6-week inpatient trial. During this time, double-blind doses of cannabis and opioids will be administered. The goal of the project is to determine if cannabis can alter the drive/desire to take opioids.

This study is testing whether brain activity related to learning can help predict how well teens respond to a treatment program designed to reduce cannabis use. Teens ages 14-17 will complete a brain scan and then take part in 10 weekly virtual sessions where they report cannabis use and complete drug tests at home. Participants can earn prizes for staying cannabis-free.

The Stanford REACH Lab's SMART TALK: Cannabis Awareness and Prevention Toolkit is a free, online educational resource to be used by educators to increase knowledge and awareness of cannabis and reduce use among youth. The aim of this study is to investigate the extent to which the curriculum changes middle and high school students' intentions to use and actual use of cannabis.

This pilot study will investigate the potential of repetitive transcranial magnetic stimulation (rTMS) to strengthen a neural circuit critical for maintaining abstinence in adolescents and youth with cannabis use disorder (CUD).

This study aims to evaluate a mobile app designed to promote the safe use of cannabis among adult users in Quebec.

This study will examine how a moderate dose of THC affects mood, stress responses, and cognitive functioning in regular cannabis users. The study uses a double-blind, placebo-controlled, crossover design, meaning each participant will complete two sessions. Specifically, each participant will be given active cannabis (20 mg THC) in one session, and placebo in the other session. The order will be randomized across participants, so half will receive cannabis first, and the other half will receive placebo first. Ninety adults who use cannabis at least weekly will be recruited from the local community. After an online screening survey, eligible participants will attend a laboratory visit where the participants will provide informed consent and complete saliva and urine drug tests to confirm recent abstinence from cannabis and absence of other drugs. Participants who pass screening will complete baseline questionnaires of cannabis use patterns, depression, anxiety, ADHD symptoms, emotion regulation, affect, and demographic information. Cannabis and placebo materials (obtained from NIDA) will be vaporized using a Volcano vaporizer device. Participants will inhale the vapor under supervision, and neither the participant nor the researcher assessing outcomes will know which product is administered. After vaping, participants will complete repeated mood ratings, saliva samples, and a battery of cognitive tests assessing executive functions like planning, inhibition, working memory, and cognitive flexibility. Participants will also complete a standardized stress challenge (the Maastricht Acute Stress Test), which involves repeated trials of placing their hand in cold water and doing challenging mental math, followed by additional mood ratings and saliva samples. The participants will then watch a nature video and report their feelings of awe and affect. At the end of each session, participants will remain in a supervised room with entertainment and snacks until at least four hours have passed since vaping and the participants report feeling sober. The participants will then return for a second session with the opposite study condition (THC or placebo) one week later. Both sessions follow the same procedures. Participants are fully debriefed after completing the study.

The central hypothesis is this: Brain circuits most relevant to cannabis use in schizophrenia are distinct from pathways identified in healthy controls who use cannabis. This study seeks to provide evidence that targeted stimulation of the DMN leads to both altered network activity and a concomitant behavioral change in cue-induced craving and cognitive performance in individuals with schizophrenia and schizoaffective disorder, while targeted stimulation of the L DLPFC leads to these changes in healthy controls who use cannabis. This study will test a model that integrates brain network pathophysiology and cognition to 1) explain the prevalence of cannabis use in schizophrenia and 2) identify a target for engagement in schizophrenia. This study seeks to establish a neuroscientific framework to guide future treatment-oriented studies aimed at reducing craving and improving cognitive performance in individuals with schizophrenia and schizoaffective disorder. This is a study of the effect of 2 rTMS interventions on functional connectivity and craving in individuals with schizophrenia or schizoaffective disorder and healthy controls who use cannabis. Aim 1: Target Engagement: Determine if rTMS manipulates functional connectivity of each target (DMN, L DLPFC) (n=100). Aim 2: Clinical Efficacy: Determine if rTMS affects cue-induced craving and if craving change correlates with change in functional connectivity (n=100). As an exploratory analysis, the factors that explain individual variance in rTMS-induced connectivity change will also be explored.

The purpose of this research is to determine the extent to which oculomotor function accurately detects THC-impairment, if cannabis use experience impacts this detection threshold, and to examine how the oculomotor index corresponds to a measure of sustained attention. A double-blind, placebo-controlled, within-subjects crossover design will be used to examine the dose-effects of THC (0, 5mg, 30mg) on oculomotor performance tasks and a sustained attention task in frequent and infrequent cannabis users. Results from the study will advance the investigators' understanding of the effect of THC and cannabis use frequency on oculomotor function and sustained attention, and will directly inform the validity of the investigators' oculomotor platform for identifying acute THC- induced impairment in frequent and infrequent users.

In the U.S., legal cannabis is frequently advertised as an effective treatment for mental health problems such as anxiety and depression-particularly online. States that have legalized cannabis have not implemented regulations to address this type of advertising. This project aims to investigate the influence of psychotherapeutic advertising claims (PAC) and mental health warning labels (WL) on online cannabis purchasing behaviors among light-to-moderate cannabis users with symptoms of depression and/or anxiety. The specific aims are to determine whether PAC increases cannabis purchasing intentions and whether a mental health WL can mitigate this effect. A realistic online cannabis shopping experience will be simulated using the digital Platform for Online Evaluation of Marijuana Marketing and Sales (POEMMS). The study will employ a between-subjects experimental design by randomizing 2,000 participants to one of four online stores that vary in PAC and WL content: (1) a control claims (CC)-only store, (2) a PAC store, (3) a WL store, and (4) a PAC + WL store. Participants will browse and select items as if making real purchases. Analyses will examine three primary outcomes to determine the influence of PAC and WL on purchasing behaviors: (1) total milligrams of THC purchased, (2) average potency (%THC) of products, and (3) overall number of products purchased. The long-term objective is to inform evidence-based cannabis policy and regulatory strategies by understanding the impact of cannabis marketing on vulnerable populations. This research is relevant to public health by addressing the potential risks associated with misleading cannabis marketing, which may lead to increased use and exacerbation of mental health symptoms among individuals with depression and anxiety. The project leverages a multidisciplinary team with expertise in addiction, mental health, epidemiology, and digital health technology. The findings have the potential to inform the development of targeted interventions and policies to reduce harms associated with cannabis advertising-ultimately contributing to better health outcomes and more effective regulation.

Cognitive impairment is well established in people with psychosis and is associated with cannabis use. The current study will investigate the neurobiological basis of cognitive change associated with 28-days of cannabis abstinence in people with psychosis and non-psychiatric controls with cannabis use. Participants will be randomized to a cannabis abstinent group or a non-abstinent control group and will undergo magnetic resonance imaging at baseline and following 28-days of abstinence. This study will help characterize the neuropathophysiological processes underlying cognitive dysfunction associated with cannabis use and its recovery which may guide the development of novel interventions for problematic cannabis use.

The goal of this clinical trial is to develop and test a brief online intervention to reduce alcohol and cannabis misuse and improve healthy relationship skills among young adult couples. The main questions it aims to answer are: * Will the intervention be feasible and acceptable to young adult couples? * Will the intervention demonstrate initial efficacy in reducing risky substance use and increasing relationship functioning? Eligible couples will complete a virtual baseline session and be randomized to intervention condition (online intervention with 3-5 weeks of self-paced modules) or control condition (no intervention). Couples will complete two follow-up surveys (post-assessment - approximately 5 weeks after baseline, 3-month). Couples in the control condition will be offered the intervention after 3-month follow-up. Researchers will compare intervention and control groups to see if there there is a difference between the groups on substance misuse and relationship functioning at post-assessment and 3-month follow-up.

Cannabis is the most consumed drug in the world and the French are the main consumers in Europe. The most recognized effects of cannabis on human health are of a neuro-psychic nature. The medical literature on the effects of cannabis on the lung in general, and on lung carcinogenesis in particular, is most often reassuring (Tashkin, Chest 2018; Zhang, Int J Cancer 2015; Ghasemiesfe JAMA Netw. Open. 2019), despite the fact that the concentration of carcinogens in cannabis smoke is higher than that contained in tobacco smoke (Moir, Chem. Res. Toxicol. 2008), and that cannabis smoking has been implicated in the occurrence of ENT cancers. Rather, research focuses on the therapeutic effects of cannabis, especially analgesics, and even on its possible anti-tumor virtues (Abrams, Jama Oncol. 2020). These reassuring data should, however, be viewed with a great deal of caution. On the one hand, the illegal nature of cannabis in most countries and its frequent association with tobacco consumption make studies on the subject difficult and often biased. On the other hand, the daily practice of oncologists, who observe numerous cases of advanced and rapidly progressive lung cancer occurring in young patients who are heavy users of cannabis, raises suspicion of an unrecognized role of cannabis in lung carcinogenesis. In a preliminary multicenter study on French patients under 50 years of age operated for primary lung cancer (Betser, ERJ 2021), we demonstrated that cannabis consumption was extremely frequent, concerning 43% of patients, but mentioned in patients' medical records only in 4 out of 10 cases, while the smoking status was always noted. In addition, by comparing people who smoke cannabis (always here associated with tobacco) to patients who only smoke tobacco or to non-smokers, we identified a different profile of lung cancers, with more poorly differentiated tumors, presenting at a more advanced stage (more T3-T4 versus T1-T2) requiring more complex surgery, and mostly located in the upper lobes of the lung. Similar research work is currently underway at Gustave Roussy (Dr Pradere-Dr Planchard, Villejuif, France) on patients with metastatic lung cancer, with a focus on overall survival and molecular profile.

The goal of this study is to investigate the effects of cannabis on brain function among adolescents with depression.

This study will examine the pharmacokinetics and pharmacodynamics of delta-9-tetrahydrocannabinol (THC)-infused chocolates, gummies, and drinks. Healthy adults (N=40) will complete 9 drug administration sessions, including an overnight stay prior to each session. Participants will consume THC containing products in a fasted state; following drug administration, the participants will complete cognitive and psychomotor tasks, subjective assessments, have blood collected, and vital signs monitored.

The purpose of this study is to determine the impact of tetrahydrocannabinol (THC) administration on motivational, subjective, and physiological effects of electronic cigarettes. The study's goals are to test demand for e-cigarettes, tobacco craving, affect, heart rate, blood pressure, expired breath carbon monoxide, and cognitive performance. Researchers will compare multiple doses of THC and a placebo in participants who smoke e-cigarettes and either smoke or vape THC in the laboratory.

The goal of this study is to learn how cannabis use and discontinuation affect sleep, circadian rhythms, and sensitivity to light. The main questions it aims to answer are: 1. Does cannabis use and discontinuation impact sleep drive? 2. Does cannabis use and discontinuation impact light sensitivity and circadian phase?

The purpose of the RECLAIM study is to evaluate the effectiveness of varenicline (sometimes known as Chantix) compared to placebo (an inactive substance) for the treatment of cigarettes and cannabis (marijuana). Varenicline is not FDA approved for the combination treatment of cigarette abstinence and cannabis reduction or abstinence. All participants will also receive counseling and access to online treatment modules during a quit attempt for cigarettes and a reduction attempt for cannabis. This study is being conducted by the Medical University of South Carolina. All procedures are conducted remotely and there is no in-person visits are needed. To qualify, participants must be 18 or older, live in South Carolina, use cigarettes and cannabis, and are interested in quitting cigarettes and reducing cannabis.

Canada reports some of the highest rates of cannabis use in our youth and young adult populations, among all the developed countries. Recent Health Canada surveys report that 27% of 16-19-year-olds and 32% of 20-24-year-olds have used cannabis in the past 30 days, with 16-24-year-olds showing the highest rates of daily or near-daily use. Unfortunately, cannabis use has also been found to be a risk factor for the development of a psychotic disorder in emerging adults, and in those who develop psychosis and continue cannabis use, there is a significant effect on long term outcomes. This includes the severity of symptoms, risks of relapse (being hospitalized) and not reaching a level of functioning that would be expected. Lifetime experience with cannabis is greater than 80% in young adults with early phase psychosis (EPP; the first 5 years of a psychosis illness) with up to 30% of Canadian EPP patients meeting criteria for a diagnosis of cannabis use disorder (CUD) at entry to care. A recent Canadian population-based study found that cannabis use disorder associated to psychosis has risen from 3.7% pre-2018 to 10.3% at present. There has been a significant increase in Δ9-tetrahydrocannabinol (THC) levels in cannabis products available globally over the years, with popular cannabis products available start as high as 18% THC in Canada. However high potency cannabis carries a more significant risk for psychosis development, as well as higher risk for cannabis dependence and other severe mental health issues. A major gap in the research is a specific focus on cannabis potency on brain white matter (WM) in youth and young adults, and if there are any potential treatment strategies that could be used to influence any of these cannabis WM effects. To address this, a medication called metformin, that is already used in psychosis to help with side effects of antipsychotic medications, will be used as it has also shown promise to influence WM changes in other illnesses. This project is thus focused on naturalistic cannabis potency effects on WM in emerging adults in EPP (divided into three groups; those using high potency cannabis, low potency cannabis, and minimal cannabis use) and treating them with metformin for 6 months and assessing effects on neuroimaging, cognitive and clinical variables. The purpose of this pilot feasibility study is to inform the development/refinement of an intervention protocol, and not to test potential effects or mechanisms as the sample size will have insufficient power to perform an in-depth analysis. The results of this work will inform our research strategy development and assess feasibility of our novel methodological approach. Participants will: 1. Visit the clinic at baseline, 3 months (only Timeline Follow-Back Assessment administered), and 6 months post baseline to complete substance use and mental health questionnaires, and cognitive assessments 2. Complete an MRI scan at baseline and 6 months 3. Take Metformin every day for 6 months

Using both tobacco and cannabis during pregnancy is more common in minoritized groups and can make quitting smoking in pregnancy and remaining smoke free postpartum difficult. Investigators will test an intervention to address prenatal depressive symptoms to encourage people to quit tobacco and cannabis during pregnancy and stay quit postpartum.

The study will test a computerized treatment with subjects ages 13-17 years who are seeking treatment for alcohol and/or cannabis use. Follow-up assessments will be conducted at one- and three-months following treatment.

This prospective cohort study aims to investigate factors associated with psychiatric symptom severity in participants diagnosed with methamphetamine-induced psychotic disorder (MP) with and without lifetime cannabis use (LCU). Participants hospitalized at Elazığ Mental Health and Diseases Hospital who meet Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, Text Revision (DSM-5-TR) criteria for MP will be included. Participants will be divided into two groups based on the presence or absence of LCU. Psychiatric symptoms and clinical characteristics will be assessed weekly during an eight-week inpatient follow-up period using standardized psychometric instruments. The study aims to determine whether LCU influences the course and severity of psychiatric symptoms in MP and to identify environmental, individual, and familial factors associated with symptom progression.

Brief motivational interviewing intervention to address alcohol use among diverse teens 12-17.

The goal of this study is to disentangle relationships between acute cannabis use and withdrawal on proximal depression and suicide risk and recovery in adolescents ages 12-18 years by incorporating time-varying patterns of substance use, mood, and SI. This project aims to guide the development of scalable, individualized, accessible, and affordable interventions aimed to reduce depression and suicide risk among adolescents.