Increased Risk of Schizophrenia in Youthful Users Is Another Reason for the FDA to Regulate Marijuana
By Greg Ganske
November 7th, 2025
Today’s marijuana weed is significantly stronger than when the Baby Boomer generation of the 1970s and 1980s smoked marijuana in college. Back in those days the amount of tetrahydrocannabinol (THC), the psychoactive compound in cannabis that causes the “high,” was 1-3% in marijuana.
Even as recently as the 1990s a typical joint contained only about 5% THC. Today cannabis flower alone often contains 20-30% THC.
This huge increase in potency is due to genetic selection and advanced growing techniques. Today’s cannabis products, especially concentrates like that used in “dabbing” which uses concentrates like waxes, oils, and shatter (a butane hash oil—BTO), can reach THC levels approaching 90%.
A small amount of these high concentrate substances produces a strong and immediate high with effects of euphoria and relaxation. However, the high levels of THC also can produce anxiety, paranoia, panic attacks, and an increased heart rate.
This is particularly worrisome in teenagers. Depression and anxiety are byproducts of frequent marijuana use in the young besides symptoms of delusion. Adolescence is a critical period of brain development when the brain is so-called plastic, developing neuro connections.
Using marijuana during this time interferes with the endocannabinoid system which plays a role in regulating emotions and cognitive functions.
A new study in April’s JAMA Psychiatry on marijuana and psychosis is being widely reported in the press (Ahrens, “Convergence of Cannabis and Psychosis on the Dopamine System, JAMA Psychiatry, April 9, 2025).
By using a type of MRI, researchers from McGill University discovered a dose-dependent rise in dopamine signals corresponding to the severity of Cannabis Use Disorder (CUD) symptoms that mirror those seen in untreated psychosis.
The paper showed an association, not necessarily a cause, of a biologic link between cannabis use and the risk of developing a psychosis. It suggests that cannabis use could accelerate the onset of schizophrenia.
This study provides strong neuro-biological evidence supporting the association between cannabis use and psychosis risk that is seen in longitudinal studies from Sweden, the Netherlands, Germany, France, Australia, and New Zealand (World Psychiatry. 2008, Jun; (2) 68-71.)
The most plausible hypothesis of this association is that cannabis use, especially frequent use with high doses of THC, may precipitate schizophrenia in young persons who are vulnerable because of a personal or family history of schizophrenia. One of these studies speculated that 13% of cases of schizophrenia could be averted if all cannabis use were prevented.
It is not surprising that marijuana abuse in adolescents (10 to 19 years of age.) is a risk factor for schizophrenia. It is well established that alcohol abuse in adolescents is a risk factor that can trigger mental illness in vulnerable individuals.
There is strong evidence of a complex and bi-directional relationship between alcohol abuse and schizophrenia with both genetic and environmental factors playing a role. Early alcohol use can also trigger the illness in adolescents.
The adolescent brain is still developing, and frequent and heavy alcohol use can disrupt the development of the impulse and control center in the prefrontal cortex. Alcohol, like marijuana, also has effects on the dopamine system. Excessive drinking can induce alcohol-induced psychosis (AIPD) leading to hallucinations and delusions.
Some cases of AIPD evolve into chronic, schizophrenia-like syndromes. As with marijuana, studies have shown a “does-dependent” relationship between alcohol use and mental health symptoms. As with marijuana, the risk and severity of symptoms increases with the frequency and intensity of use. Neurological changes caused by early drinking may persist in adulthood.
In light of increased knowledge of the association of marijuana use with mental illness, it is a matter of public health for the FDA to regulate marijuana just as The Alcohol and Tobacco Tax and Trade Bureau (TTB) regulates the production, labeling and advertising of alcoholic beverages and as the FDA regulates tobacco.
In September 2012 and August 2022, I wrote two opinions on marijuana in the Des Moines Register (“It is Time to Legalize Recreational Marijuana in Iowa and Nationally” and “I Still Think Marijuana Should Be Legal: Moderation In All Things”). I advocated state and federal legalization primarily to provide a legal marijuana product that is free of lethal drugs such as fentanyl.
In the United States cannabis is legal in 40 of the 50 states for medical use and 24 states for recreational use. The patchwork of state-by-state regulations is problematic. Regulating marijuana products under the FDA’s rigorous review process would ensure they were safe from heavy metals, bacteria and mold, and pesticides that have been found in both the illegal and legal cannabis supply.
These contaminants pose a significant health hazard for both recreational and medical users. Because of the current Class 1 classification of marijuana grouping, it with narcotics and dangerous drugs the FDA and the EPA has not provided guidance on regulating contaminants to the states. This has left the states to determine helter-skelter on their own how to protect cannabis users.
Federal legalization would allow for traditional research and drug development processes ensuring that marijuana products are safe and effective for their uses. FDA oversight would prevent misleading claims about cannabis products. We need better research on whether cannabis really is effective. For instance, does marijuana provide effective pain relief for multiple sclerosis or does it actually cause unfavorable side effects?
Legalization would help ensure accurate labeling on potency and potential side effects. The FDA could issue warnings like those seen on tobacco products, especially for high-potency concentrates and cannabis-infused food and drinks.
Regulation of tobacco by the FDA has controlled nicotine content and the FDA is currently proposing further reduction in nicotine. Its public relations crusade against tobacco products has been effective in reducing tobacco use.
The FDA should similarly devise a national advertising, educational and prevention campaign warning about the abuse of marijuana and how it could lead to mental health disease especially in the young. Such campaigns have been effective for instance in warning pregnant women about the dangers of drinking alcohol.
Legalization would generate tax revenue that could be used to fund public health programs on the dangers of marijuana abuse. Federal legalization would end the conflict between federal and state laws. Congress would need to act on this as well as the FDA reclassifying the Controlled Substance Act classification of marijuana.
I would envision setting up a separate FDA division for marijuana similar to that I proposed in legislation back in 2000 which eventually served as a basis for the Tobacco Control Act of 2009.
In the meantime, parents and doctors should be advising young individuals to avoid using cannabis. At a minimum, they should counsel delay marijuana use until at least early adulthood. If a child starts experiencing unusual behaviors such as isolating, talking to themselves, or hearing or seeing things that others don’t, psychological treatment should be sought right away. Marijuana use might be involved.
Warning—this isn’t your grandmother’s weed anymore!
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Greg Ganske, MD, Member of Congress (ret), is a retired plastic surgeon who cared for women with breast cancer, children with cleft lips, farmers with hand injuries, trauma and burn patients. He served Iowa in Congress from 1995-2003 on the committee with oversight of the FDA and EPA.
Comments 31
Marijuana is legal only because there is tax money to be gained for the government regulating and controlling the sale of marijuana. Except for medical reasons for the use of marijuana (pain relief for one), it just a money-making scheme for politicians to buy votes. Dedicating the money from the government taxes on marijuana for education about the dangers of marijuana is a great idea, but the politicians will use the money to buy more votes or fund healthcare for illegals. Remember, the lottery revenues were to go to education to relieve the pressure on property taxes and the tolls on the Illinois Tollway were to pay off the original bonds and then the Tollway would be free for all to use. Again, the politicians hijacked those promises to buy more votes from the unions and entrench more self-serving bureaucracies.
Weed is legal only because the Pritzker Family controls the industry.
https://www.reformforillinois.org/blog/pritzkers-plan-legalize-pot-benefit-relatives-invested-industry/
If you can’t take care of family what kind of person are you?
Great article. Agreed 100%. In order to keep our highways safe, I also think they ought to do more and spend more on test development to enable police officers to test for your state of high. Every baby boomer remembers the effect on your brain when you mix smoking a joint with a few drinks.
It does not get better than the City of Evanston where they use a tax on pot shops to provide funding reparations, sort of circular when one looks at it. Provide gambling and pot for the wretched of the earth and lower test standards in education for the illusion of progress. Math proficiency for black students in Evanston High School is 12.4%.
In “Brave New World” the masses were fed “soma” to mollify t heir passions and appease their instincts. We should have learned the meanings and warnings from great literature like Huxley’s book, but the you have to be able to read and comprehend. No…go have another gummie and lotto ticket, you will do better on the next lowered education standard.
Another column of healthy journalism and policy diagnostics by the most helpful doctor around, Greg Ganske. Another insightful Comment by James Jennings, this time deftly bracketing Evanston vacuity and Huxley wisdom.
Hey, savvy JKN this morning is specially appreciated after my mistake of looking at a Chicago newspaper’s front page pushing all far-left propaganda before I clicked over to its good Chicago sports coverage (not accessible in my cheese-focused market ). By the way, have they smoking been smoking something off-brand in Chicago news offices?
Thank you, I had to look up the meaning of “vacuity,” very appropriate. Not only is the local print media beyond the pale, I used to like the interplay of Robin, Larry, and others on WGN TV in the early morning but the WGN news leads the media pack in their wokeness. One of their grossly obese Karen WGN producers became famous by exposing her unsightly keister to the world after attacking ICE and being taken to the ground…the lingering sight of it almost sent to a shrink for PTSD. She is the “face” of WGN news.
I also enjoyed their interplay on WGN, however the narrative they are pushing has become unwatchable for me. We will see if CBS actually becomes more balanced, of course would that ever get down to a local level?
James, I envy your strong stomach in being able to witness ugly idiocy. In the broadcast of that Brandon-berserk protest against four-years-overdue law enforcement, you actually watched that Karen keister ? Ick. If that’s the “face” of WGN News, then what is the . . . oh, never mind.
Superb. Thank you. I worked with adolescents with mental health issues in the 1980s, and we could see, even then, how smoking weed altered their overall mental (and physical) health, even before legalization increased potency.
As it is not going away any more than Prohibition made alcohol go away, regulation and labeling is absolutely necessary.
Nice article. The Highland Park shooter and the Aurora Colorado movie theatre shooter were both heavy marijuana users.
Great informative column Doctor G. Just a sad state of affairs, so many of our young are on anti depressants and other medications and smoking cannabis has to have some effect. What will be the long term effects when these people reach middle age?
A few years ago, right after Chicago legalized marijuana I was out late and a car drove by with numerous individuals and a foreign odor emanated from it. A smell like a chemical fire. I asked the person I was with if that was what is being sold on “dispensaries ” and he stated it was. When I was a teenager back in the eighties marijuana had a smell like burning leaves, if you ever raked leaves and burned them you know what I mean. The whiff of what I got from the car was like burning motor oil or burning plastic. Back in the days of the Underground Economy the stuff was grown in an open field by various Third World people who grew the stuff under the radar. Sometimes there was stronger stuff cultivated by experienced growers using modern growing techniques. Getting stuff like that was rare. Now the stuff they’re foisting on the public is massively more potent in its THC content, grown in controlled environments by corporate entities. It doesn’t smell organic at all and you’ve highlighted the ways this stuff is being chemically enhanced by the corporations selling this stuff. All designed to fry your brain. Mancow Muller joked that the lead in Chicago water is making black people violent and the weed that the city sells made white people STUPID. Could be some truth there from what I’m seeing. Isn’t it funny that the things that they used to lock up mobsters for are now part of Democrat State economies. Gambling. Check. Drugs. Check. Prostitution, (soon to be a) Check. There are various entities that are pushing for legalizing “sex work”. See, if you clean up the terms dope houses become “dispensaries” . Prostitution becomes ” sex work”. It’s all in the terminology you are using. It scrapes off all the rough edges and makes it more palatable for the masses…
Eye opening article. Great comments above from well informed readers.
Doc,
Spot on piece. I said long ago that legalizing pot was going to cause more people to lose their marbles, drive high, and go bonkers. But there’s too much tax revenue in it, and consequently all these states couldn’t refuse the boon. After all, their attitude has been thus far, “keep em all dumb and stupid” and they’ll continue to vote our way! Apparently it’s working in some states, especially right here in Illinois!
Typical politician (former) BS response. TAX IT. IT WONT WORK GREG, IT WONT WORK. MONIES WILL BE USED ELSEWHERE. What’s next? Taxing prostitution?
ALL ILLICIT DRUGS ARE BAD. So is alcohol and smoking of any kind. Alcohol has been proven beyond doubt to be carcinogenic, ie it is metabolized to acetylaldehyde a well known potent carcinogenic. But idiots continue you to drink, smoke & eat like pigs.
Want to stop use. Take away health care for users of any of this stuff. Why should I pay elevated premiums for fat people and drug addicts of all kinds.
I grew up in my grandfather’s bar/tavern. I’ve seen first hand as a kid and MD what drugs (that’s what ETOH is) do to one’s body. There is no value to any of this stuff.
Disagree Mr. Rudd-
IMO there there is a legitimate place for moderate use of alcohol, weed, gambling, unhealthy food, risky behaviors, an occasional cigar, strip clubs, . . . all the vices actually – I would never want to live like the Taliban!
Almost everything in life has risks. Leaving home to drive to work has risks.
As a general principle I believe that we, the people, have the right to make our own decisions, so long as our decisions don’t infringe upon the rights of another’s.
They call that Freedom.
But agreed it’s often difficult to determine that point where one person’s decisions begin to infringe upon another’s.
Regarding your resentment to having to pay “elevated premiums for fat people and drug addicts of all kinds” well that is a slippery slope if I ever heard one!
Taking for example those “fat people” that you don’t want to pay for – what % overweight do you, Dr. Rudd, deem acceptable? How about exercise- do you have a certain minimum level in mind before someone is worthy of being covered on your health plan?
I agree Bob. It seems as if Dr. Rudds’ vision of the ideal society aligns perfectly with that of the Taliban. Ha Ha.
Wise words Dr. Ganske. The stuff out there now is definitely not your grandmother’s weed and it is high time to face reality. We should establish reasonable guidance, oversight, and regulation of Cannabis at the Federal level. In the meantime can’t we just take smaller hits? 🙂
Excellent column…as one who has had experience as a pot smoker (I no longer do) it’s become interesting to see how the gradual legalization has manifested into yet another political flashpoint. If I’m not mistaken, it’s still illegal enough that federal funding is not available. The tug-of-war continues. Much has been said about how Prohibition led to the emergence of organized crime – with no real accomplishment to stop them”evils of alcohol”…seems like we’re staring into that prism again. If people want something they’ll find a way to get it. If regulating marijuana leads to safer levels, and perhaps more intelligent usage then I’m all for it.
This is a good piece. Thank you Dr. Marijuana is legal because it is very popular and the government can get a cut. The dispensary licenses are handed out to connected people largely. They may have a black face or a female, or a lesbian on the letterhead, but a fat pink guy is making most of the profit.
Regulation of this industry is much needed. These high potency products are decidedly unhealthy and dangerous. In the 70’s, most pot was grown outside and the THC level was much lower. As Mr. Diaz stated , it even smelled differently. It is far more potent and potentially harmful than the relatively benign plant that was demonized in the 50’s.
I see this as an even larger societal contagion however. Marijuana, Ritalin, anti depressants, video games, other garbage on the internet is being used to an aesthetize the minds of our young people, especially our boys.
We have scores of young men at home, “Taking care of mom”, or living in the basement, not working, watching porn, reading filth and lies on the web, becoming bitter, maybe even being persuaded to join a cult, or go out and commit violence,
Marriage rates have dropped, there are fewer eligible men than women. Birth rates are falling, In NYC, there are just as many abortions as live births.
As Dr. Rudd stated, heavy use of any drug is unhealthy, including alcohol. We need more education, like they did with cigarettes. These high potency products need to be banned, and if you’re going to consume, it would probably be better to grow your own anyway.
Pritzker needs to be exposed, along with his whole family. They sponsor trans, drugs, lax law enforcement, funnel money to non profits, NGO’s and the like, they pay a fraction of taxes compared to the an average W2 worker.
He has spent hundreds of millions to get into office and influence our elections. He’s a businessman. Does anyone out there think he’s not getting a return on his investment?
So, again, I must ask. Wouldn’t it be worth trying public financing of campaigns? Open up the political process to get more middle class people involved? I still remember as a young man living in Massachusetts. John Kerry debated William Weld in the US Senate race to replace a retiring Senator. He was asked by the moderator why is he spending millions of dollars to gain an office that only paid 130,000 dollars a year. He couldn’t give a cogent response.
The billionaires are eating us out of house and home, literally and figuratively. They fund extreme leftist and right wing ideology, push drugs and alcohol on us, and want to keep us under their control. Keep us divided, keep us fight, numb, anesthetized with drugs.
This whole left/wing. culture war is a con being played on us.
You think all these illegals are here solely because of Biden? Follow the money. They are all in our pockets.
One Eyed Jacks abound.
Those talking about the legalization of pot being about taxes etc are missing the point. Milton Friedman said we should legalize drugs, not for the tax dollars but to bust up cartels and the illegal things that they cause, like crime. He never said we shouldn’t regulate a legal substance.
Big difference and nuance in the point.
That being said, today’s pot is polio pot. You don’t do anything after you smoke it….just sit on the couch and stare. I don’t know from experience but have noticed it over the years from people I see who use it.
I agree with this good article. Legalizing federally and regulating like cigarettes is the least worst option now that the genie is out of the bottle. The additional tax revenue will never be worth the human costs. As said elsewhere, ensuring people are not driving stoned should be a priority as well.
Overall I thought Dr. Ganske wrote a great article. But I d
In fact you could argue that the higher potency makes today’s cannabis safer because you don’t have to inhale as much toxic smoke to achieve a desired effect. Likewise, a person can get just as drunk on wine as whiskey, even though whiskey is several times more potent. I believe it all comes down to personal responsibility. Most anything can be harmful if it’s overdone to the point of stupid. Even water.
Great comment.
Thanks Bruce. We don’t always agree, but sometimes we do. And I think that’s the beauty in all of this.
The libertarian in me says no to regulation, but if the government had never done so with tobacco, how many more would be dead today from lung cancer? Had they not passed safety regulations for cribs, the meat packing industry?
Our host just wrote about Combine scumbag George Ryan who sold drivers licenses to people who could not even read English and were not citizens.
I can see if it never directly affected you, you might not think it was a problem. This is what liberals do. They take up for illegal aliens and get all bothered about their rights and not right of folks like the Willis family.
Should we chalk up Fentanyl use to personal responsibility?
This pot and the high potency are part of a bigger social contagion. I say have the mob grow it in the Forest Preserve like they did in the old days, just like Vegas, it was better when they ran it.
Grow it yourself in your yard if you want to partake. Chemical free, but not near the tomatoes as it does soak up the nutrients.
“The paper showed an association, not necessarily a cause, of a biologic link between cannabis use and the risk of developing a psychosis. It suggests that cannabis use could accelerate the onset of schizophrenia.”
To think King Crimson’s song from 1969 “21st Century Schizoid Man” (at least the title…) would be so prescient in these modern times…
An irrelevelant aside: “In The Court Of The Crimson King” ranks at least top 3 in Best Album Covers Ever, regardless of what you think of their music.
The real loss here, tragic loss – is the art, the tradition of shared smoke.
I wrote a blues number in high school I called “low glowing bowl”
Back when you could pass a bowl around six or seven times before it was cashed.
Talk, tell stories and develop most excellent friendships.
Like American Indians camped outside of Brandon Johnson’s “only Indians” Chicago, would pass the pipe with white settlers.
Gone. I miss it
I appreciate all the thoughtful resonses to my article and thank John and Betty Kass for publishing it. I find the commetary to the articles on this site to be particularly thoughtful.
They reflect an informed, respectful, courteous readership free of personal invective seen on other sites. Greg Ganske
Being familiar with its effects on mental acuity and physical motor skills, I don’t want to be on the highway or in a car with anyone under its influence.
I do trust the current growers, or even pot smokers also on SSRIs, before I trust the guidance of our FDA.