What's Wrong with Marijuana?

Here’s a medical miracle for you: a drug that relieves pain, reduces anxiety, improves your mood, and has no side effects.

Too good to be true? Well, millions of Americans believe that drug is marijuana.

Are they right?

I’m a physician, board-certified internist, and addiction medicine specialist. I’ve treated thousands of people whose addictions to opiates, alcohol, and other drugs were wrecking their relationships, their careers, and their lives. And I’m telling you marijuana can be both harmful and addictive, just like many other substances.

What I’ve seen firsthand for twenty years is now becoming obvious to other doctors and researchers: increased use of marijuana is leading to increased psychosis, bipolar mania, and even spontaneous vomiting, especially in adolescents and young adults. The younger the user, the less developed their brain, the more harmful the drug. 

I hate to burst your bubble, but that is the science.

A 2022 Gallup survey found 30% of Americans between 18 and 34 use marijuana. When scientists at the University of Michigan asked young adults between 19 and 30 if they’d used it within the past month, 29% said yes in 2021, compared to 21% in 2016 and 17% in 2011.

Daily marijuana use across all ages nearly doubled from 6% in 2011 to 11% in 2021. That translates into over 13 million Americans, compared with 5 million in the decade before.

There is no such thing as a “bad” drug. They are just molecules that affect the human physiology. Most Americans use some form of a recreational substance. But ignoring or denying potential adverse effects creates the potential for serious harm. There is no free lunch with mother nature so there are always side effects. My goal here is not to shame or scare anyone, but to raise awareness so you can make informed decisions.

Speaking of that, keep in mind that marijuana has gone corporate. According to Forbes, legal marijuana is now a 20 billion dollar industry and growing. There’s a lot of vested interest in making sure you don’t hear the bad news.

But there are risks. And the more you use, and the higher the concentrations, the more the risk.

Of course, most people who use marijuana won’t have a psychotic break, develop bipolar disorder, or become schizophrenic—just as most people who drink don’t develop alcoholic liver disease or alcohol dementia.

Some individuals—and not a small number—will have a significant reaction to marijuana. And there is no way to know in advance. You won’t know until it happens. And then it might be too late.

It wasn’t always like this. The marijuana people use today is not the weed of my generation. It hasn’t been for at least two decades.

What changed?

The answer is found in three letters: THC 

THC or tetrahydrocannabinol, is the main psychoactive—or mind-altering—component of cannabis; it’s what gets you high.

Keith Humphreys—a Stanford University professor of psychiatry and drug policy adviser to Presidents Bush and Obama—testified to a Rhode Island state senate committee that THC concentration had increased from 3% in the 80s up to over 20% in 2017. According to the New York Times in 2023, that figure is now nearing 100% THC—a thirtyfold increase.

And as the stuff gets stronger, so do its effects.

The 2021 National Survey on Drug Use and Health found that among the 52 million Americans 12 and older who used marijuana in the past month, 16 million were addicted. So nearly one-third of users can’t quit—at least, not without help—despite the drug’s negative effects on their lives. 

In 2023, JAMA Psychiatry published a study of marijuana habits among 6.5 million Danes over the age of 16. The study found that marijuana addicts were twice as likely as nonusers to be diagnosed with clinical depression and up to four times as likely to develop bipolar disorder with psychotic symptoms.

A study in Norway also published in 2023 concluded that among people who had no pre-existing mental health issues who had a psychotic incident after using marijuana, 27 percent developed what has been characterized as schizophrenia.

Are you with me? One out of four perfectly healthy people who started using marijuana on a regular basis developed a severe mental disorder.

Some of them were my patients. Two of them were family members. One developed an addiction, one psychosis. They’re now both fine, but required treatment. They are among the lucky ones.

But others weren’t so lucky. 

Joshua Jimenez started using at 14 and was hospitalized three times for marijuana-induced psychosis. He committed suicide in 2021; he was 22.

Kevin Bright was 15 when he started using marijuana to allegedly self-medicate for depression. Three years later, he suffered his first psychotic break. He ended his life at age 29.

Joshua and Kevin are not simply anecdotes.

A 2023 JAMA study found that cannabis-linked attempted suicides have increased at an average rate of 17% a year.

Still want to take that miracle drug that relieves pain, reduces anxiety, improves your mood, and has no side effects?

I’m Dr. Drew Pinsky for Prager University.