Marijuana Policy Patchwork Not Based on Science, Experts Say

Federal laws hobble research into the dangers, and the potential benefits, of the drug.
Mark Frankel (left) moderated a question-and-answer period with marijuana policy experts. | Juan David Romero/AAAS

As a physician and a scientist, J. Michael Bostwick values logic and scientific evidence. But when the Mayo Clinic College of Medicine professor first immersed himself in the topic of marijuana, he says he found very little of either.

“I want to underscore my exasperation. When I set out to try to understand this topic, I couldn’t find logic,” said Bostwick, who spoke at a 30 March Neuroscience & Society event co-sponsored by AAAS and the Dana Foundation. “I couldn’t find logic in the law, in the way the federal government was acting, or in the way the states were acting. It was very frustrating.”

When marijuana was outlawed in 1970 and classified as a Schedule I drug—signifying that it had a high potential for abuse and no scientifically proven therapeutic value—it had not been significantly studied. Similarly, with 23 states and the District of Columbia currently implementing a hugely wide range of state laws allowing marijuana’s use as medicine and even as a recreational drug, scientific studies demonstrating its medicinal properties, as well as its risks, are still lacking, Bostwick said.

“I would contend that cannabis was ‘scheduled’ in the absence of science,” said Bostwick, “just as there’s a problem now with the lack of science.”

For researchers who would provide scientific evidence of marijuana’s potential benefits and dangers, the plant’s classification as a Schedule I substance creates huge obstacles.

“The Drug Enforcement Administration has to give you a registration,” said Nora Volkow, director of the National Institute on Drug Abuse (NIDA), who is noted for her research on addiction. “I know from researchers that this has been very, very difficult. Whether you are studying cannabidiol for the treatment of seizure disorders or for analgesia, it is a slow process.”

“I think everyone on the panel agreed,” said event moderator Mark Frankel, director of the AAAS Scientific Responsibility, Human Rights and Law Program, “that we need more research conducted by more scientists, but that federal policy impedes those efforts.”

Cannabidiol (CBD) is one of the most closely observed substances derived from the marijuana plant. It has shown promise in medical treatment, particularly for controlling seizures. Unlike the other most well-known compound in marijuana, delta-9-tetrahidrocannabinol (THC), CBD is not euphorigenic, meaning it does not create a “high.” To make further research on CBD less cumbersome, Volkow said that she advocates classifying the compound in a less rigid category than its marijuana parent plant.

“I have continuing dialogue with the [Food and Drug Administration], trying to figure out ways in which we can make research easier, such as scheduling cannabidiol,” Volkow said. “I’m very much for facilitating research on cannabis and changing some of this scheduling of these substances.”

Some Schedule I substances, such as heroin, have related counterparts, such as morphine and oxycontin, that are less regulated.

Volkow said that she does not advocate the legalization of marijuana. She made the point that legal drugs, like tobacco and alcohol, can have hugely detrimental effects on individuals and on society, but their legality grants them a certain societal acceptance that may invite more young people to try them. At the same time, some studies have shown that marijuana use at an early age can affect brain development, impair cognition, and lessen motivation.

“If you are smoking marijuana as a teenager,” Volkow said, “trust me, your educational achievement is going to be signficantly worse.”

Volkow explained that the brain and the body have their own endocannabinoid system. “Just like we produce endogenous opioids and endorphins that make us high, we also produce endogenous cannabinoids that make us feel good, create a sense of well-being. So what cannabis is doing is just binding to the receptors that are there in our brains.” The problem with using marijuana, Volkow said, is that “you saturate your system in ways that are not physiologically relevant, and that triggers neuronal adaptations in the brain and also in the body, which can result in adverse consequences and, in the case of the brain, can lead to addiction.”

Still, Volkow acknowledged that more controlled studies are needed to understand marijuana’s addiction potential and possible impairment of the brain, especially the developing brain. “In the field, there have been many, many studies, and all of them can be questioned because certain parameters were not controlled,” Volkow said. “As a result of that, we are in a situation where we are vulnerable to criticisms of the robustness of the findings.”

In response, NIDA, in partnership with other branches of the National Institutes of Health, has launched the Adolescent Brain Cognition and Development research effort, a longitudinal study that will follow 10,000 children from ages 8 to 21 to assess the effects of marijuana, nicotine, and alcohol on their brains. The results of the study, however, will not be available for 10 years, and in the meantime, other research efforts are stymied, said Bostwick.

“We’ve really begun to understand the endocannabinoid system and how potentially important it could be, like any other neurotransmitter system, for coming up with medications that might be able to be used,” Bostwick said. However, he added, “It appears there is no end in sight to this federal-state standoff, and the result is that a protean source of potential pharmaceuticals is moribund.”

AAAS and the Dana Foundation have collaborated on the Neuroscience & Society lecture series since 2012, with 15 events reaching 2700 attendees. The purpose of the series is to provide a public forum for members of the community to hear outstanding speakers address the status of brain research and what it might mean for ordinary individuals, as well as for society. This article originally appeared in AAAS News & Notes in the 29 April 2016 edition of Science.