The Marijuana Debate

Neuroethics Viewpoint
Philip M. Boffey
September 6, 2019
scientist examines plant

There has been a huge increase in legalization and use of cannabis (marijuana) in recent years. Despite federal prohibition of all cannabis use, 33 states and the District of Columbia have legalized marijuana for medical purposes; 11 of them and DC have further legalized it for recreational uses, and 15 other states have decriminalized marijuana use to some extent.

Each step raises ethical issues for health care providers, patients, and government officials.

The case in favor of using marijuana for medical purposes was made in a letter from the World Health Organization to the secretary general of the United Nations on January 24, 2019. Some 30 countries around the world had legalized medical marijuana as of 2018.

The letter followed an expert committee’s conclusion that cannabis and cannabinoids derived from the marijuana plant are relatively low risk and carry positive health benefits, including pain reduction and improvement of motor functions in patients with Parkinson’s. It called for more research to better evaluate the benefits and harms.

The letter recommended that cannabis be removed from the most restrictive category under a 1961 convention on narcotic drugs but left in a less restrictive category that would still control its use. This was because of “the adverse effects associated with long-term cannabis use, including increased risk of mental health disorders, such as anxiety, depression, and psychotic illness.” The WHO called regular cannabis use “particularly problematic for young people, because of its effects on the developing brain.”

Proponents of marijuana have a moral imperative to protect teenagers from exposure to products that could permanently harm their mental capacities.

An expert committee appointed by the National Academies of Sciences, Engineering and Medicine also raised some red flags about marijuana use in a report issued in January 2017. The panel considered more than 10,000 scientific abstracts published since 1999 and reached almost 100 separate conclusions.

Therapeutically, it found evidence that cannabis or cannabinoids could reduce pain symptoms, the muscle spasms associated with multiple sclerosis, and the nausea and vomiting caused by chemotherapy. On the downside, it found suggestive evidence that cannabis use prior to driving increases the risk of a motor vehicle accidents and, in states where cannabis use is legal, increased the risk that young children would find and ingest the substance in overdose quantities.

Parents and other adults surely have an ethical obligation to keep cannabis out of the reach of children.

Evidence reviewed by the committee suggests that cannabis use is likely to increase the risk of developing schizophrenia, other psychoses, and social anxiety disorders, and to a lesser extent, depression. However, the panel acknowledged that the link between marijuana and psychosis is complex and may be multidirectional. Marijuana may not cause psychosis; some other factor may promote both marijuana use and psychosis, or psychotic illnesses may cause some individuals to use marijuana.

The panel found “moderate evidence” that cannabis can lead to abuse of other substances such as alcohol, tobacco, and illicit drugs. It also found “limited evidence” that cannabis can impair learning, memory, and attention, even in individuals who have stopped smoking cannabis. It can also impair subsequent academic achievement, social relationships, and may increase the risk of unemployment and low income.

The panel cited a recent nationwide survey which estimated that 22 million Americans aged 12 and older had used marijuana in the last 30 days and that 90 percent of the adult users used it primarily for recreational purpose while only 10 percent used it solely for medical purposes. Around 36 percent used it for both purposes. This is an alarming increase in the recreational markets where oversight is minimal.

The risks of rapid expansion have been documented in Colorado, the first state to legalize recreational marijuana. Edibles there produced a disproportionate share of pot-related crises in emergency rooms, according to a report in The New York Times on March 25. Edibles were also more likely than inhaled pot to cause severe intoxication, acute psychiatric symptoms in people with no history of psychiatric illness, and cardiovascular problems. The lead author of the report, published in the April 16 issue of the Annals of Internal Medicine, told reporter Roni Caryn Rabin that he does not think edibles should be available in the retail recreational market.

Meanwhile, the state medical societies in New York, New Jersey, Connecticut, and Delaware issued a joint statement in March opposing the legalization of recreational marijuana because there is not enough research proving it is safe.

Even though two-thirds of the states have legalized marijuana for medicinal purposes, enrolling some two to three million people in their programs, the vast majority of health care systems won’t provide cannabis to their patients or allow them to bring their own supply. The facilities are reluctant because cannabis remains classified by the government as a schedule 1 drug, making it technically illegal to use for any purpose, including medical.

In a blog posted by the journal Health Affairs on July 23, the commissioner and assistant commissioner of the New Jersey Department of Health cited evidence that when physicians prescribe marijuana, the authorities tend to look the other way. They proposed four different ways that health care facilities could accommodate patients. The Mayo Clinic in Rochester MN already allows patients to bring cannabis along with other drugs they are taking at home.

The greatest risk to public health is probably posed by cannabidiol oils (CBD) added to edible food products, such as cookies and brownies. The problem is that CBD is not psychoactive and does not cause the highs characterized by THC. It can take hours before it kicks in, so users may mistakenly believe it isn’t working and eat some more, compounding the risk. The edibles may also contain too much or too little of the supposedly active ingredient or contain toxic contaminants introduced during production, which is not tightly regulated by the Food and Drug Administration (FDA).

The FDA has taken some steps to police the market. Last year it approved an oral solution of Epidiolex, a purified form of CBD, to treat certain severe childhood epileptic disorders. But in April it sent warning letters, in collaboration with the Federal Trade Commission, to three companies making “egregious, unfounded” claims that their products were likely to limit or cure cancer, neurodegenerative conditions, or other diseases. The FDA initially wanted to subject food and dietary supplants containing CBD to its usual, careful review process that can take years. But after vociferous complaints from politicians and industry that the cannabis market is expanding so rapidly that faster action is needed, the agency agreed to expedite the process.

Scott Gottlieb, who resigned as FDA commissioner in April, has suggested that the agency could approve some CBD products immediately based on petitions submitted by individual producers that CBD will be present in very low concentrations unlikely to pose a health risk. That could relieve the political pressure while allowing more time to fully evaluate the risks and benefits of this rapidly expanding universe of cannabis products.

Phil Boffey is former deputy editor of the New York Times Editorial Board and editorial page writer, primarily focusing on the impacts of science and health on society. He was also editor of Science Times and a member of two teams that won Pulitzer Prizes.

The views and opinions expressed are those of the author and do not imply endorsement by The Dana Foundation.