Lawmakers challenge professor’s controversial cannabis presentation

Prune Marijuana Plants ways. Harvesting and Processing Commercial cannabis
A known cannabis prohibitionist compared the drug to crystal meth.

Tuesday morning’s House Professions & Public Health Subcommittee meeting on medical cannabis quickly turned tense as a Harvard Medical School professor gave a presentation condemning the use of high-potency cannabis.

Representatives were quick to question professor of psychobiology Bertha Madras‘ assertions, including one in which she linked cannabis and psychiatric symptoms among youth, including schizophrenia.

“People who go into the emergency department with psychosis, due to their initiation into marijuana use, and they continue to use, they’re more likely to convert to full-blown schizophrenia, and the conversion rate is between 20% and 40%,” she said.

However, scientists are split on correlation and causation, which Madras acknowledged, meaning there is no backing to suggest cannabis use causes schizophrenia. Representatives challenged Madras for seeming to present the link as cause.

According to the Centers for Disease Control and Prevention, “use of marijuana at an early age can affect memory, school performance, attention and learning; conclusions have been mixed regarding its impact on mental health conditions, including psychosis, depression, and anxiety.”

“I’m not sure if I should start running for the hills, or running for a dispensary to relieve my anxiety around so much of what’s been presented,” said Rep. Carlos Guillermo Smith. “We have to be very careful about not conflating there being a causality here. … Currently, we have a medical cannabis program, but we already know that the physician needs to basically acknowledge that the benefits outweigh any of the risk.”

Smith took his discontent with the presentation to Twitter, writing that the “so-called ‘expert'” was “pushing misinformation.” He added that Madras “also doesn’t even believe cannabis is medicine” and linked to an op-ed she penned in The Washington Post.

“Why are we listening to her again? Where are the credible experts?” Smith continued.

In another tweet, Smith lamented that Madras is a “known cannabis prohibitionist” and a member of the Federalist Society and that she was pushing “bogus studies.”

The overuse of cannabis, just as the overuse of caffeine, nicotine, alcohol, stimulants and hallucinogens, can cause psychosis, according to a report from The New York Times. Psychosis is defined as a symptom — temporary disorientation often accompanied by paranoia or an ominous sensation.

It should be noted that Madras acknowledged the consequences of high-potency cannabis “are not well described yet because this is a new phenomenon.” One study she used to discuss the correlation was from an observational report at the Bengal Insane Asylum in 1895 that reported 25-40% of patients there a had long history of marijuana use.

“It was far more prominently associated with marijuana than with alcohol or with opioids,” she said. “This is long before marijuana became a political issue, an entrepreneurial or a medical issue.”

Madras also expressed concern over the increased use of high-potency cannabis by young people, since children with parents who use cannabis are about three times more likely to use it themselves. Her concern is exacerbated by the increased legal use of dispensaries, which may allow more adults access to cannabis.

Madras said high-potency use among young people is associated with addiction, psychosis and use of other substances.

“It’s not healthy for young people,” Madras said. “High potency is associated with more brain changes, addiction, psychosis and hospitalizations. … One of my primary concerns is multi-generational use, because that is a very significant problem. The highest increases in marijuana use over the past decade, have been in young adults of childbearing and child-rearing age.”

Smith pointed out to Madras that a CDC study from 2019 looking at Colorado, Oregon and Washington — all states that have legalized recreational marijuana — found no statewide increase in youth marijuana use following retail legalization for adults.

“There is not unlimited access for this population that we’ve heard obviously a lot about our youth,” he said. 

Smith went on to ask Madras, who served as one of six commissioners on former President Donald Trump’s Commission on Combating Drug Addiction and the Opioid Crisis, if she maintained her opinion she shared in a Washington Post Op-ed arguing that medical cannabis is not medicine.

“I subscribe to the very simple principle — if a drug has gone through a rigid, FDA process for every criteria … and the FDA has approved it, I would lean on it as a medicine,” she responded. “I still subscribe to my Washington Post Op-ed.”

“It’s unheard of in other forms of medical practice to have shatters and dabs and, and cereals and lollipops and cupcakes and gummy bears and so on and so forth,” she said.

Madras also drew criticism from Rep. Michele Rayner via Twitter after the professor compared cannabis to crystal meth or crack cocaine.

“There’s always a push towards making things more potent,” she said. “The motivations for increasing the percentage of THC, the potent component of it, are very, very obvious. I think it’s the same motivation to develop crystal meth or crack cocaine and spirits.”

Rayner called the professor “dangerous,” and “irresponsible.”

Christopher Ferguson, the director for Florida’s Office of Medical Marijuana Use, also presented at the meeting to provide updates to the committee on the state’s medical cannabis program.

In 2020, Post-traumatic stress disorder was the office’s most diagnosed qualifying condition, accounting for 36.3% of patients.

The office also experienced a busy year. In June and July, the office had to hire additional staff to assist with call volume and processing applications. As of Feb. 12, Florida has 2,644 qualified physicians who can recommend cannabis use and 485,693 active patients approved for the drug.

Kelly Hayes

Kelly Hayes studied journalism and political science at the University of Florida. Kelly was born and raised in Tampa Bay. A recent graduate, she enjoys government and legal reporting. She has experience covering the Florida Legislature as well as local government, and is a proud Alligator alum. You can reach Kelly at [email protected].


  • Ron Ogden

    February 16, 2021 at 2:19 pm

    Two Representatives, out of 15. Say, what political party do they belong to? Doesn’t tell in the story. Howcum? What did the other members of the subcommittee say? A Harvard Medical School professor. Ms. Hayes, are you familiar with the phrase “follow the science”? Used to see that a lot from Dems on such things as “climate catastrophe”. Not in this case, huh?

  • Palmer Tom

    February 16, 2021 at 10:03 pm

    reefer madness lives with these charlatans. Legalize and tax.

  • Gary J Stein, MPH

    February 17, 2021 at 3:50 am

    Regarding the Bengal Study. You cant start with a population that already has a condition for which you are seeking a cause, because you have no control group. Cannabis users being rtreated for psycosis does not qualify the cannabis as the agent of change, since you have no gage as to how many folks that don’t have it develop psychoses.
    Ane in 1895 there were politial issues with cannabis, since we were trying to work with Hcina to mitigate the diplomatic fallout of the Chinese Exclusion Act of 1882, and we were negotiating wit the Chinese to help them with their opium use epidemic, and were being pressured to develope our own narcotic laws, and cannabis was considered a narcotic. So Dr. Madras is also a poor historian.

  • Charlotte Greenbarg

    February 17, 2021 at 11:15 am

    I can’t help wondering if the legislators who denigrate a Harvard professor have any financial interest in the cannabis industry. And the word is not “exasperated “. It’s “Exacerbated”

  • Manny Johnson

    February 17, 2021 at 7:05 pm

    So much grandstanding and searching for an audience isn’t doing anyone any good. Professor Madras should do her own clinical studies and listen to her patient’s words and medical improvements instead of always quoting other’s research. Our team had the honor to serve as a SME to several legislators preparing for this presentation who wanted to see the real scientific and medical studies on medical marijuana. Please note that the federal prohibition on Cannabis (Hemp and Marijuana) through NIDA, the National Institute on Drug Abuse, allowed only studies that showed the danger of Marijuana. It’s very easy to find the thousands of anecdotal reports from all over the world about the Safe and Effective benefits of Marijuana as a medicine for a variety of diseases. It’s “obvious” why certain legislators brought the above person mentioned here because they obviously have never read or listened to a respected scientist on this very important issue. Please stop wasting tax dollars paying “experts” who only want to present agendas that virtually no other scientist with proven knowledge and experience will reinforce is just throwing money away… taxpayer money. Please don’t forget these legislators with their hands out when they beg for reelection. Love and Light to the Truth!

Comments are closed.


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