Ryan McLaughlin, PhD: Challenges Studying Cannabis to Treat Psychiatric Illness

In the past few years, research has expanded on studying cannabis as a treatment option for psychiatric illness.¹

Just last week, NBC News reported the Biden administration will soon announce an interim role reclassifying cannabis for the first time since 1971, when the Controlled Substances Act began.²

The Drug Enforcement Administration has proposed to reclassify marijuana from Schedule I—the classification of the drugs heroin, methamphetamines, and LSD—to Schedule III. The proposal acknowledges the substance’s potential medical benefits. With cannabis currently being classified as Schedule I, the substance is not accepted for medical use, unlike Schedule III substances such as Tylenol, steroids, and testosterone.

It will take time before Cannabis switches to the Schedule III classification as the proposal needs to first be published in the Federal Register, followed by a 60-day public comment period. After that, an administrative law judge can hold a hearing before the rule is approved.

In an interview with HCPLive, Ryan McLaughlin, MD, assistant professor of integrative physiology and neuroscience at Washington State University, described how the distribution of CB1 and CB2 receptors which bind to cannabis molecules influence physiological processes. He explained the receptors target areas such as movement, motor control, memory, appetite, immune regulation, and inflammation.

Even though the government is making moves on changing the classification of cannabis to allow for medical use, research on treating psychiatric illness with cannabis presents ethical challenges. McLaughlin discussed said challenges.

“We would want to ideally design a study where you have a randomized placebo controlled double blind study: this is the gold standard in human research,” McLaughlin said. “When you're trying to evaluate the efficacy of a novel drug, but with cannabis, it's ethically impractical to actually dichotomize groups or split people randomly.”

He explained how investigators cannot just randomly select 1 participant to be a cannabis user and another to not be a cannabis user to follow over time.

“It's difficult,” he said. “We have to really rely on quasi experimental and correlational studies to try and gain insight into how cannabis is affecting all these sorts of things.”

He added another challenge of researching cannabis includes the fact “no real patenting of plants to that degree” exists.

“There's less of an impetus from drug companies to push very expensive and lengthy clinical trials for whole plant cannabis products,” McLaughlin said. “They would much rather use drugs that are in early development that kind of target the same system, but don't actually have intoxicating effects the same way that cannabis does. So we just aren't quite there yet with the field.”

McLaughlin has no relevant disclosures.

References

1. ^{McLaughlin, R. Talking With (and Listening to) Your Patients About Cannabis. Session presented at: American Psychiatric Association (APA) 2024 Annual Meeting. New York, NY. May 5, 2024.}
2. ^{Tsirkin, J and Alba, M. Biden Administration Plans to Reclassify Marijuana, Easing Restrictions Nationwide. NBC News. April 30, 2024. https://www.nbcnews.com/politics/joe-biden/biden-administration-plans-reclassify-marijuana-easing-restrictions-na-rcna149424. Accessed May 6, 2024.}