Cannabis is now legal for medical use in about thirty American states, and recreational use of the drug is legal in nine. But there’s still a lot we don’t know about its potential therapeutic effects. Jeff Chen, MD, is the director of the UCLA Cannabis Research Initiative, one of the first academic programs in the world dedicated to studying cannabis. But despite growing legalization and popularity among Americans, cannabis research remains restricted because it’s a Schedule I drug (the same classification as heroin).
The rising consensus: We need to study the plant to find its potential medicinal benefits. And perhaps it will now be easier with the Medical Cannabis Research Act of 2018, which allows for more licenses to grow research-quality marijuana for scientific studies. The proposed bill, if enacted, would also support more federally approved clinical trials.
The medical marijuana market, by some estimates, could be worth $50 billion by 2025 as pharmaceutical companies inject more cash into the industry. But this, Chen says, is being done without good data to support it. Without regulation that lifts constraints off of researchers like Chen, though, we may never have sound scientific evidence of the benefits—or downsides—of marijuana.
(A quick word before we get to Chen: If you’re curious about cannabis, be sure to check the laws in your state and, as always, bring any health q’s or concerns to your doctor first.)
How far has medical cannabis research come? What are the challenges today?
Can you give us a rundown of the recent Medical Cannabis Research Act and how that affects your work?
The bill does two things: It forces the federal government to increase the number of federally licensed producers of cannabis. Currently there is only one, the University of Mississippi, and it’s been the sole licensed producer for half a century. The second thing it does is allow VA health care providers to inform their patients about federally approved clinical trials of cannabis. Previously, federally approved clinical trials of cannabis that involved veterans—such as Dr. Sue Sisley and Dr. Bonn-Miller’s clinical trial of smoked cannabis for post-traumatic stress disorder—had difficulty recruiting veterans because the VA would not allow their employees to advertise the study to veterans.
What are the misconceptions surrounding medical cannabis?
The biggest misconception is that you have to get “high” to get a medicinal benefit. In many studies of cannabis or cannabinoids for pain, folks were getting pain relief with minimal to no psychoactivity. In fact, at high doses, THC can actually make pain worse.
What current research are you focusing on? What are you excited about?
We have more than a dozen studies looking at the impacts of cannabis on the aging brain, how to treat adolescents who are abusing cannabis, how CBD can treat pediatric neurologic diseases, how cannabinoids can treat autoimmune diseases like lupus, etc. We are also developing some of the world’s first human studies on the use of cannabis and cannabinoids to treat opioid use disorder, to prevent or slow Alzheimer’s disease, and to increase survival in cancer patients. However, again, locating funding to launch these studies has been difficult.
One area that we are particularly excited about is understanding how cannabis compounds may be able to reduce opioid use in chronic-pain patients, reduce opioid withdrawal symptoms, and prevent relapse in folks who are recovering from opioid use disorder. We realize we are in our nation’s worst opioid epidemic in history, and it’s incredibly urgent and important that we apply modern science to cannabis and understand if it could play a role in helping the opioid epidemic.
What do we know about medical cannabis so far?
First off, there have been no randomized placebo-controlled studies of cannabis done in humans for most of the conditions that people anecdotally use cannabis for. Right now, the state of the evidence is largely limited to animal studies and observational studies, neither of which are reliable. Time and time again, what we see in animal studies doesn’t pan out for humans. And the results from observational studies are subject to large placebo effects, which are even stronger for cannabis because of its “miraculous” reputation.
The conditions we do have good human data for benefit are chronic pain, nausea and vomiting related to chemotherapy, muscle spasticity in multiple sclerosis, and certain pediatric epilepsy conditions. Yes, cannabis is addictive (both psychologically and physically), although most people who use cannabis do not develop addiction or cannabis use disorder. And the data we have on the abuse potential and health risks of cannabis are largely drawn from studies looking at recreational use of high-THC cannabis that was combusted and inhaled. What we don’t know is if those risks are similar or different for other types of cannabis and ingestion methods—for example, someone who is medically using a high-CBD cannabis product that is orally ingested.
What do we know about the side effects of cannabis when taken with other medications?
Both THC and CBD may interact with other medications. For example, THC may decrease blood levels of antipsychotics or antidepressants and decrease their effectiveness. On the other hand, CBD may boost blood levels of benzodiazepines, antidepressants, antipsychotics, blood-thinning medication, etc., which could increase toxicity and side effects from these medications. Thus, it’s important to tell your doctor about the cannabis products you are using so they can monitor for any potential interactions with your other medication.
How does your research help guide regulation and policy?
Regulation and policy are intended to maximize public benefit while minimizing risk, so our research provides the data for informed decisions. Unfortunately, because research has been stymied for half a century, right now there isn’t a lot of good data to guide cannabis policy and regulation.
This plant can be understood, but it will take considerable time because of the hundreds of compounds within it and the multitude of ways to consume it. The future of cannabis is where we understand what types of cannabis or combinations of cannabinoids, at what dosage, using which consumption method, for what type of person, with which disease, could provide benefit or could harm them. We are particularly concerned about the risks of cannabis to certain vulnerable populations, like folks with mental health issues, adolescents with developing brains, and pregnant woman.
We’ve commonly heard the comment that marijuana is a plant and therefore can’t be dangerous. What’s your response to this?
There are lots of dangerous and poisonous plants. Heroin is made from the poppy plant. Nightshade can kill you. Cannabis is not harmless, but its harms have been overstated in the past, like in the movie Reefer Madness.
Jeff Chen, MD, is the founder and executive director of the UCLA Cannabis Research Initiative. He has spent the past four years working at the intersection of academia, industry, the nonprofit sector, and government to accelerate research into the health effects of cannabis. He graduated magna cum laude from Cornell University, where he studied biology, business, and music, and he is a graduate of the specialized dual-degree MD/MBA program at UCLA.
This article is for informational purposes only, even if and to the extent that it features the advice of physicians and medical practitioners. This article is not, nor is it intended to be, a substitute for professional medical advice, diagnosis, or treatment and should never be relied upon for specific medical advice.