Researchers at Drexel University are undertaking the first large-scale NIH-funded study of marijuana use among young adults aged 18 to 26.
Led by School of Public Health associate professor Stephen Lankenau, a team will for five years follow 390 marijuana users in Los Angeles.
Half of the participants will have prescriptions for the drug and obtain it from legal dispensaries, while the remaining will be recreational smokers.
At the heart of the study is the "gateway theory," which proposes drugs like marijuana prompt users to progress to "harder" substances.
Lankenau said that's not necessarily the case – preliminary findings from an earlier pilot study he conducted seemed to indicate medical marijuana patients generally abused other drugs at lower rates than recreational smokers, suggesting it may not be the pot itself that can precipitate a downward spiral, but the network of dealers those who obtain it illegally must navigate.
"One hypothesis that we're testing is for medical marijuana patients, if they have access to dispensaries and a whole range of marijuana products, whether their overall patterns of illicit drug use are lower, compared to recreational users," Lankenau said.
"That's kind of the idea behind the dispensary, that it can provide social support and may destigmatize marijuana use."
Lankenau said, especially given the dearth of federal funding for marijuana studies in the past and the growing number of states who are now legalizing the stuff, it's important to conduct research to further inform pot policies, and to do it now.
"Given the increasing number of states that have legalized marijuana, [the NIH] realizes that this is becoming a national issue," he said.
"Unless you start now, you're going to get behind the curve and there will be all sorts of individuals who will be using medical marijuana, but there won't really be any kind of robust studies that will be able to indicate, 'Is this a good policy or not?'
"And that's really, fundamentally, what we're interested in by looking at young adults in Los Angeles – determining whether this is a good policy, particularly for young adults."
• Beginning in October, administrators will begin to enroll participants by approaching young people on the street in areas of Los Angeles with a large number of dispensaries.
• Participants will answer a questionnaire, then complete one follow-up interview each year for four years.
• Forty patients will be chosen for more in-depth, qualitative interviews about their personal histories and experiences with drug use.