15 Things the Cannabis Industry Doesn’t Want You to Know

As an emergency and addiction physician practicing on the front lines of the emergency department, I am seeing firsthand the devastating damage marijuana causes.

“It’s just weed.”

Those are the words that still haunt the parents of Johnny Stack.

Johnny was intelligent, funny, and charming with a 4.0 GPA and a college scholarship. Living in Colorado he was recruited into the marijuana scene at a young age, changing his personality and resulting in cannabis induced psychosis. His parent’s thought it was “just weed,” but quickly realized it was anything but. Johnny had hallucinations; he thought the mob was chasing him and he ran off a building to his death. He was 19.

Johnny Stack died from cannabis induced psychosis.

Brian Smith loved weed. Then the vomiting began. The teenager and his mother couldn’t believe what the doctors said was causing his dreadful abdominal pain and vomiting: smoking weed. He developed cannabis hyperemesis syndrome (CHS), also known as scromiting (screaming and vomiting). Months later, it killed him. He was 17.

I am an emergency and addiction physician who practices on the front lines of the emergency department. I had the honor to serve as the first Chief Medical Officer at the White House Office of National Drug Control Policy. Every shift I, along with my colleagues across the United States, treat patients with marijuana poisoning. CHS and Cannabis Induced Psychosis are the most common marijuana associated daily diagnosis in emergency departments across our country.

I learned the painful way that the Jewish community is not shielded from the harms of marijuana poisoning.

Aryeh was found dead by his parents in Boro Park, New York. His Hassidic mom was shocked. “He just used weed,” she told me, thinking it was an innocent habit. But Aryeh was poisoned by a blue M-30 fake OxyContin pill that contained deadly fentanyl and no oxycodone. Aryeh’s marijuana addiction led to misusing other drugs. He made a mistake that cost his life.

I spoke to the detective on the case and there were four similar deaths in the insulated religious community that same weekend. The taboo and stigma of drug use kept things quiet, allowing the deaths to spread.

Illicit fentanyl is an opioid 100 times more potent than morphine. Over 150 people a day die of illicit fentanyl in the United States; it is the number one cause of death for ages 18-45. Treating patients who overdosed on fentanyl and want treatment for fentanyl addiction, I have not met any that did not start priming their brain with marijuana before getting into fentanyl. It’s not “just weed.”

While marijuana and drug use in America is being normalized and commercialized, most people do not use marijuana, contrary to common belief. 65% of Americans aged 18 – 25, the highest age group of marijuana user, have not used marijuana in the past month.

It is a value in Judaism to live a healthy life and take care of your body. The Talmud derives from the verse “be very careful to safeguard your soul” (Deut. 4:15) a mandate to be responsible with your life and not harm your physical body.

Here are 15 things about marijuana that the cannabis industry doesn’t want you to know. You deserve to understand the risks. I hope this science-based information helps you make healthy and protective choices.

1. Today’s marijuana is not just a plant – it is genetically modified, potent and contains toxins

“This ain’t your mama’s marijuana” said Surgeon General Jerome Adams. The cannabis products sold at dispensaries have been genetically altered for a high percentage of THC, making the drug very potent. The marijuana plant of 1995 averaged 4 % THC. Today’s plant products are more than four times more potent, with THC levels as high as 17 – 40%.

Marijuana is also sold in food and drink products at high potency. Concentrate cannabis products such as shatters, dabs, and oils are made in a lab and can have THC concentrations of nearly 90% – that is like smoking over 100 joints from 1995. That is why today I treat marijuana poisoning every shift, while I never saw such cases when I was a young doctor.

2. Marijuana can have contaminants and toxins.

The cannabis industry is poorly regulated. The public has no FDA protection or protective standards, allowing for various toxins, carcinogens, and contaminants. In a study from UC Davis, 20 out of 20 legal dispensaries were found to have contaminants in their plant-based products. Fungal contamination of cannabis flower is well known. This prompted the CDC to issue a warning against smoking cannabis for organ transplant recipients and those with other immunocompromising conditions. People who are immunocompromised should not be smoking or vaping cannabis products.

The marijuana plant has over 400 chemicals and can include toxins such as heavy metals like lead and mercury as well as carcinogens.

3. The drug industry targets youth

It is well known that the tobacco industry targeted youth. Big tobacco learned that younger age of onset and higher nicotine content, increases addiction, and therefore increases profits. Big marijuana has learned and improved upon Big tobacco and sells candies and drinks that targets children and young adults.

While the legal age is 18 or 21, the scientific age for an adult brain is 25 – 27. Addiction is up to 7 times higher for a growing brain than an adult brain. We would have less addiction if the population abstained for any addictive substance until age 25.

4. Marijuana stunts brain growth 

The brain continues to grow until the mid-20s by synaptic pruning and myelination. Synaptic pruning is a selection process where the brain keeps pathways that are used and cuts out pathways that are not used. The young period of time is a critical to learn and develop strong healthy neuronal pathways. A pathway into marijuana steals away other healthy pathways.

Myelination is the white coating of neurons. The last part of the brain to develop myelin is the frontal lobe. The frontal lobe is the executive function of the brain in charge of decision making, motivation and judgment.

Marijuana stunts the growth of the brain. That is why the Surgeon General issued an advisory on marijuana and the developing brain, especially young adults and during pregnancy.

5. Marijuana is Addictive

Cannabis use disorder or addiction is defined using the same DSM V 11-point criteria as alcohol use disorder or opioid use disorder. Three out of 10 cannabis users develop addiction, but those starting before age 18 are 7 times more likely to develop addiction.

Cannabis withdrawal is reported by up to 30% of regular users and in 50-90% of heavy users. Many cannabis users do not believe they suffer from withdrawal until they understand that the symptoms of cannabis withdrawal are different than alcohol or opioid withdrawal. The common symptoms of cannabis withdrawal are irritability, anxiety, insomnia, headache, and significant cravings for marijuana. Typically, these symptoms last for about two weeks after cessation.

6. Marijuana is a risk factor for psychosis and schizophrenia

As a physician I can write a prescription for FDA approved THC, the psychoactive ingredient in marijuana in the form of dronabinol (Marinol) with a maximal dose of 20 mg (less than half of a 1990 marijuana joint). The listed FDA warning for dronabinol for low dose THC includes neuropsychiatric adverse reactions.

High potency THC has a greater association with psychosis, a symptom of misinterpreting reality by hallucinations, delusions or paranoia. Large European studies associated high potency THC, defined at over 10% concentration in plant-based products, with 5-fold increased odds ratio of developing a psychotic disorder. A study published in Lancet of 10 studies including 7390 patients showed a dose-response between frequency of cannabis and risk of psychosis. Furthermore, states with liberal cannabis laws have increased psychosis associated with cannabis.

Not everyone who smokes tobacco will develop cancer, heart disease or emphysema, but it is a known risk factor. Similarly, marijuana is a risk factor for psychosis which can turn into permanent schizophrenia.

7. Marijuana targets the heart

While the brain is the number one target for THC, the heart is number two. The FDA label for pharmaceutical grade THC, dronabinol, includes cardiac toxicity. Patient with cardiovascular disease should be cautioned about cannabis use related to their individual medical diagnosis, per the American Heart Association. This follows, as high potency THC behaves as a stimulant. There are associations with heart attack, stroke, and irregular heart rhythms.

8. Marijuana can make you scromit

Cannabis Hyperemesis Syndrome (CHS) is associated with long-term cannabis use, typically of smoked product. They symptoms of CHS have been described as “scromiting,” screaming and vomiting. There are reported deaths with CHS caused by electrolyte imbalance. This problem is based on inundation of THC on the cannabinoid receptors over a long period of time causing the neurons to act irradicably. The cure for cannabis hyperemesis syndrome is cessation of marijuana use, which is easier said than done since people with this disorder most likely have an addiction.

9. Marijuana is not safer than alcohol

One of the common talking points of Big Marijuana is that it is safer than alcohol. While there is no doubt alcohol is a health hazard, scientifically and medically they are different. They don’t need to compete on who is worse, in fact they are addictive and cause more problems when used together.

Alcohol is a water-soluble chemical that leaves the body in zero order kinetics. Young adults with alcohol poisoning sober quickly in a few hours. Marijuana is a lipid or fat-soluble molecule that goes to the brain and sticks around for a while.

Furthermore, there are no receptors for alcohol in the brain or body, while the brain and body have many cannabinoid receptors that can be altered by marijuana. People who drink alcohol or get drunk rarely develop psychosis at a young agePsychosis associated with marijuana can happen at first use or after several times and happens at a younger age.

10. Marijuana is not safer than tobacco

Smoking and vaping of any product is bad for your lungs. Smoked cannabis products can contain similar toxins to tobacco products. In fact, vaping cannabis is worse for the lungs than tobacco.

A study compared second hand smoke from a Marlboro cigarette, a marijuana joint, and a vape, found that a marijuana joint produces 3.5 times as much secondhand smoke as a Marlboro cigarette.

radiology study compared the CT scan of chronic marijuana smokers, verses tobacco smokers and non-smokers. The CT findings for marijuana smokers showed the worst effects.

11. Marijuana is not recommended for pain

The majority of people who use marijuana as medicine, claim it helps with pain. Howevercannabis is contraindicated in patients who have an opioid use disorder according to the American Society of Addiction MedicineConcurrent marijuana and long-term opioid use does not improve pain. Cannabis use increased the risk of opioid use disorder in a study of 34,653 participants.

12. Marijuana is not recommended for seizures

There is false and dangerous messaging that marijuana is good for seizures. In fact, it decreases the seizure threshold and increases the risk of seizures. CBD, cannabidiol, is available in prescription form as Epidiolex, and is recommended for a select subset of babies with a rare seizure disorder called Dravet Syndrome or Lennox-Gastaut Syndrome. These babies are not smoking pot or using any type of THC products. CBD is pharmacologically distinct from THC.

13. Driving while using marijuana can be deadly

People may think driving under the influence of marijuana makes you drive slow. That may have been true 15 years ago, but today’s pot is more potent and acts as a stimulant. Traffic fatalities involving cannabis are often associated with high speed according to my discussions with prosecutors.

Drugged driving is a public health issue that is growing. A study of 191 regular cannabis users tested driving ability in a simulator after smoking marijuana. It took 4.5 hours to return to baseline, although the driver perceived that they were not impaired.

Overall, marijuana users were about 25% more likely to be involved in a crash than drivers with no evidence of marijuana use. Marijuana legalization resulted in a 5.8% increase in injury crash rates and 2.3% increase in fatal crash rates.

If you smoke marijuana, wait at least 4.5 hours before getting behind the wheel. Like with alcohol, refuse to be a passenger of an impaired driver.

14. Babies are being poisoned

Sadly, the number one poisoning in children under the age of six is marijuana. Marijuana poisoning for this age group has increase 13.3 fold from 2004 to 2018 with 15% of requiring ICU care. Two babies a day are being treated at the San Diego Children’s hospital for marijuana poisoning. The most common culprit is marijuana gummies.

Adults over 65 have suffered an increase of 1804% of emergency visits related to marijuana poisoning between 2005 and 2019. Older adults tend to be on medications that have drug interactions with cannabis products or have impaired renal or liver function that slows metabolism. People have suffered hemorrhage because of cannabis interaction with their blood thinners. Check out Drugs.com drug interaction and enter cannabis for THC or cannabidiol for CBD to learn of the hundreds of drug interactions.

15. Weed whacks your DNA

Marijuana is genotoxic, meaning it can damage your DNA. Several studies have shown that cannabis can alter male sperm DNA that is associated with autism. Cannabis has been linked as a teratogen causing congenital abnormalities to exposed fetus. It is also associated with a rise in pediatric cancers.

For the protection of the next generation, you may want to abstain from cannabis for 3 months before conceiving.


Substance use disorder is a chronic relapsing disease of the brain that is treatable. If you or someone you know is struggling, please reach out for help. Treatment is possible.

Fentanyl has been found in all the illicit drug supply. Therefore, if you are around someone who uses drugs, any drugs, you should carry naloxone, the opioid reversal agent. If you need a prescription of naloxone, you can get one for free at Dr. Lev’s website, Hightruths.com. It should be covered by insurance even if it is not for you.

To learn even more about marijuana from a medical library, visit IASIC1.org, the International Academy on the Science and Impact of Cannabis.