The purpose of this investigation was to assess the prevalence and consequences of substance use in US medical students and to examine medical students’ views of substance-use policies and programs provided at their institution. Our findings indicate that 91.3% and 26.2% of medical students consumed alcohol and used marijuana respectively in the past year. One third of medical students (33.8%) consumed five or more drinks in one sitting in the past two weeks. Consequences of student alcohol and drug use in this sample of medical students included but were not limited to interpersonal altercations, serious suicidal ideation, cognitive deficits, compromised academic performance, and driving under the influence of substances.

In the most recent comprehensive study conducted 25 years ago, students reported using the following substances within 30 days of data collection: alcohol (87.5%), marijuana (10%), and cigarettes (10%) among many others with lower prevalence [7]. Students in our study reported consuming alcohol (91.3%) and marijuana (11.7%) at slightly higher rates, although the use of tobacco (6.8%) slightly decreased. Comparatively, those in the general population with ages ranging from 18–25 and 26 and older reported rates of alcohol use within the past month at 59.6% and 56.5% respectively [1], which is notably lower than medical students of similar ages in this investigation. Consistent with other studies, we found that male medical students tend to consume significantly more alcohol than their female peers [4]. This pattern remained when comparing our sample to age matched peers in the general population; both male (87.8%) and female medical (83.9%) students in the current sample consumed alcohol in the past 30 days at higher rates than male (72.8% of 21–25 year olds; 69.3% of 26–34 year olds) and female (65.4% of 21–25 year olds, 59.7% of 26–34 year olds) respondents in the general population [18].

Our finding that one third of medical students had five or more drinks in a sitting within the past two weeks mirrors previous data on alcohol consumption of medical students [19], but revealed a much lower rate than that found in a recent single-institution study that included a lower threshold for at-risk drinking [5]. Note that this finding also serves as a conservative estimate, as our threshold for at-risk drinking was five drinks per sitting (rather than four) for female respondents. We used this threshold to maintain the psychometric support of the Core Alcohol and Drug Survey [11]. Thus, our study may have underestimated the rate of at-risk drinking due to our use of a conservative measure.

Similar rates of marijuana use have also recently been reported [5]. This finding is concerning because marijuana potency is stronger than it was 25 years ago [20]. Although our study suggests consumption has not drastically changed over the past 25 years, research suggests that heavy drinking and marijuana use patterns may be higher at individual medical schools than that found in national samples [5,7,21].

Our findings provide empirical evidence that medical students frequently experience personal and academic consequences of substance use during medical school. Serious consequences associated with alcohol and drug use were reported: 22.3% experienced memory loss, 5.8% had seriously considered suicide, 24.1% reported doing something they later regretted, 18.9% reported getting into an argument or fight, and more than 10% admitted that they had driven while under the influence of alcohol or drugs. Such findings are disconcerting, as this group of consequences suggests that substance use in medical students frequently precipitates severe lapses in professionalism [4,8,22,23], and too often endangers the lives of not only the student who is using but the lives of peers and others they may care for in the future.

Three quarters of students in our study did not know whether substance policies were enforced, and nearly half of the participants reported feeling that the school is either neutral or unconcerned about substance use and abuse at their medical school. Despite decades of alcohol and drug use awareness campaigns that often take place as early as middle school [24], these findings reflect a nearly two-fold increase over the past 25 years in the proportion of students who are unaware of whether or not their institution has an alcohol and drug policy [7]. In addition to re-examining, redesigning, and enforcing tighter boundaries pertaining to the use of alcohol and drugs among medical students, medical schools may want to prioritize students’ mental and physical health by creating a safe environment to talk about substance use and its consequences without the fear of backlash, and to both provide and promote services and resources for students in need of help.

Researchers have suggested that medical students who frequently use drugs or drink to excess during medical school, which includes after-exam partying, are at risk for developing a pattern of habitual use, and that this may foreshadow future consequences in residency and beyond [4,5,22,23]. The tendency to use substances to achieve mind altering effects or temporary relief from the academic demands of medical school makes these students susceptible to engaging in a pattern of risky social drinking in the future; such behavior has also been shown to affect professional decision making, such as providing alcohol counseling referrals to patients less often than those who do not drink [19].

Research indicates that substance-use behaviors predictive of substance-use disorders occur well before students enter medical school [6,8]. With early intervention and monitoring, treatment of substance use is often successful [25]. Thus, providing screening for students is a crucial area for medical education development, and one that many students are in fact already receiving during their education [26]. Curricula addressing the personal and professional consequences of substance use, as well as processes for screening, intervening, and treating substance-use disorders provide an avenue for disseminating institutional concern about the substances used by medical students, as well as alternatives to substance use. Staff and faculty may also benefit through education on the signs of medical student substance use, in addition to training on how to intervene when needed. Guided interpersonal interactions that include screening, brief intervention and referral to treatment [27], and digital resources have also been shown to be effective [28–30]. Our findings reinforce the need for all clinicians who treat medical students to obtain a complete substance-use history, including history of consequences and the possibility of co-occurring mood and anxiety disorders.

Although one would assume that medical schools have alcohol and drug use policies, many students shared that they were not aware of them. Only thirty percent of our participants were aware of whether or not substance-use prevention programs were available at their institution, even though they felt that their peers were involved in substance use at alarmingly high rates. Increasing both faculty and student awareness of guidelines, prevention, intervention, and treatment programs available to medical students is an important step for each institution to consider. Information on substance-use policies and risks can be conveyed in multiple ways to students at first-year orientation meetings, in ongoing wellness programs, in human behavior and neuroscience curricula, and in ongoing discussions between faculty and students on the risks of substance use during medical school. In addition to raising student awareness of the risks of substance use during medical education, educating faculty about medical students’ unique vulnerabilities to substance use during medical school is equally important. Ultimately, it is educational leadership that will direct meaningful solutions to the problem of medical student substance use.