IMPORTANCE Laws and attitudes toward marijuana in the United States are becoming more permissive but little is known about whether the prevalence rates of marijuana use and marijuana use disorders have changed in the 21st century. OBJECTIVE To present nationally representative information on the past-year prevalence rates of marijuana use, marijuana use disorder, and marijuana use disorder am...

OBJECTIVE To assess the prevalence and frequency of medical marijuana diversion and use among adolescents in substance abuse treatment and to identify factors related to their medical marijuana use. METHOD This study calculated the prevalence and frequency of diverted medical marijuana use among adolescents (n = 164), ages 14-18 years (mean age = 16.09, SD = 1.12), in substance abuse treatmen...

A total of 54,361 students in seventh through twelfth grades completed a survey examining the impact of perceived harm of marijuana use, ease of access in obtaining marijuana, and perceived parent/peer disapproval of marijuana use on youth involvement in annual and recent marijuana use. Results indicated that 1 in 6 (16%) students used marijuana in the past year, while 1 in 10 (10%) used mariju...

INTRODUCTION This study examined whether exposure to marijuana advertisements was associated with current marijuana use and frequency of use among US adolescents in grades 8, 10, and 12. METHODS Weighted estimates of exposure to marijuana advertisements and marijuana use from the 2014 and 2015 Monitoring the Future studies were investigated. Factors associated with the prevalence and frequenc...

BACKGROUND The average amount of marijuana in a joint is unknown, yet this figure is a critical quantity for creating credible measures of marijuana consumption. It is essential for projecting tax revenues post-legalization, estimating the size of illicit marijuana markets, and learning about how much marijuana users are consuming in order to understand health and behavioral consequences. MET...

Marijuana use among women is highly prevalent, but the societal conversation on marijuana rarely focuses on how marijuana affects female reproduction and endocrinology. This article reviews the current scientific literature regarding marijuana use and hypothalamic-pituitary-ovarian (HPO) axis regulation, ovarian hormone production, the menstrual cycle, and fertility. Evidence suggests that mari...

OBJECTIVE Marijuana abuse is associated with neurological changes including increases in frontal EEG alpha during abstinence. Research is needed to assess to what extent these EEG patterns are indicative of cerebral perfusion deficits. METHODS We recorded the resting eyes closed EEG of 75 abstinent marijuana users and 33 control subjects. Fifty-six marijuana users used marijuana for less than...

Some studies have suggested that long-term, regular use of marijuana starting in adolescence might impair brain development and lower intelligence quotient (1,2). Since 2012, purchase of recreational or retail marijuana has become legal for persons aged ≥21 years in the District of Columbia, Alaska, California, Colorado, Maine, Massachusetts, Nevada, Oregon, and Washington, raising concern abou...

It is well established that childhood maltreatment is an important predictor of marijuana use, but few studies have examined the mechanisms underlying this relationship. The current study examines marijuana motives as mediators of the relationship between childhood maltreatment and marijuana use in a sample of young adults. In addition, pathways from childhood maltreatment to emotion dysregulat...

Marijuana is the illicit drug most commonly used worldwide. The mechanisms by which this drug affects the brain have been studied exhaustively during the last 40 years, and better understood in the last decade. For example, the discovery of receptors to which marijuana binds, has been a major achievement in neurosciences and in the study of drug addiction. Moreover, the description of the endog...