Horrible Side Effects of Marijuana That People Never Talk About

With the legalization of marijuana on the rise, it’s important to note the drug’s side effects. While weed can have significant medicinal and economic benefits, if nationwide legalization occurs, the public should be informed of any negative aspects. Read on to know more about the scary potential side effects, including this one classic myth that’s a confirmed reality (page 10).


Man pouring marijuana from a canister into his hand at a dispensary.

Marijuana can increase your chances of developing schizophrenia. | David McNew/Getty Images

  • Marijuana can increase the risk of developing schizophrenia, depression, and social anxiety.

Various studies on the effects of marijuana have been done through the years, but NBC recently reported that one potential risk of the drug is a serious one — mental illness. Marijuana can increase one’s risk of developing schizophrenia. This illness causes delusions, hallucinations, and unclear thinking, and greatly affects one’s ability to function properly. The drug can also increase depression and social anxiety, according to the same study. Those who use marijuana heavily are also more likely to be suicidal.

Next: This side effect could appear by middle age.

Memory loss

Cannabis plants grow in the greenhouse

Your mind may not be so sharp after a few smoke sessions. | Drew Angerer/Getty Images

  • Those who practice long-term daily marijuana use can see memory loss by middle age.

In 2016, JAMA Internal Medicine published a study confirming that those who practiced long-term, daily marijuana use had poorer verbal memory in their middle age compared to those who didn’t smoke. The study considered “long term” to mean five years or more. The researchers examined 3,400 people’s habits over a 25-year period. Everyone in the group took a cognitive skills test at the end of the study period, which determined the results. Legalization of marijuana across the United States may result in more people smoking the drug daily for long periods of time.

Next: You might have been taught wrong


Man smoking marijuana cigarette

Marijuana can become addictive. | iStock.com/Pe3check

  • One in 11 young adults who smoke weed will develop an addiction.

Many people praise marijuana for its non-addictive qualities. However, physicians would strongly disagree with such a statement. “There’s no question at all that marijuana is addictive,” Dr. Sharon Levy, the director of the Adolescent Substance Abuse Program at Boston Children’s Hospital, told Boston Globe. Right now, only one in 11 young adults who smoke weed will develop an addiction. However, with more potent products beginning to enter the market, the addiction rates will increase. With health care that doesn’t consider marijuana a serious addiction, people may have nowhere to turn.

Next: Marijuana users are 26% more likely to have this.

Heart and stroke risk

cannibis joint and herb, marijuana

Marijuana can have health benefits, but people with heart problems need to be extra careful | iStock/Getty Images

  • Those who use marijuana were 26 percent more likely to have a stroke than those who do not use marijuana.

While it’s easy to picture a marijuana user mellowing out as they wish, marijuana can raise a heart rate by 20% to 100% shortly after smoking, and the effect can last up to 3 hours, according to Live Science and the National Institute on Drug Abuse. This may raise the risk of heart attack.

“A 2017 study by the Einstein Medical Center in Philadelphia found that those who used marijuana were 26 percent more likely to have a stroke than those who did not use marijuana,” explains Live Science. “Those studied were also 10 percent more likely to have developed heart failure.”


Next: Not all marijuana consumption is the same.

Lung irritation

smoking a joint

Marijuana smoke can irritate your lungs. | Pedro Pardo/AFP/Getty Images

  • Regular marijuana use can cause a prolonged cough, airway inflammation, and wheezing.

Although there is no conclusive evidence that marijuana causes lung cancer, it does create a series of respiratory problems in frequent users, such as a prolonged cough, airway inflammation, and wheezing. According to the University of Washington’s Alcohol and Drug Abuse Institute, marijuana smoke contains harmful chemicals that are in similar range to those in tobacco smoke. Since marijuana requires a deeper inhalation than cigarettes, it leaves about five times the carbon monoxide concentration and three times the tar in the respiratory tract compared to cigarettes.

Next: Can marijuana really lower testosterone and sperm count?


Low testosterone levels

Man smoking marijuana at a festival

Marijuana can lower your testosterone levels. | Mark Piscotty/Getty Images

  • Chronic marijuana use could lower testosterone, and potentially lead to gynecomastia.

Some studies have shown that chronic cannabis use can result in lower testosterone levels, and even a lower sperm count. Doctors have agreed that it’s very plausible that chronic marijuana use can lower testosterone. However, researchers cannot draw a completely factual conclusion until they complete several more studies. Low levels can also result in something called gynecomastia, which is caused by a hormone imbalance between testosterone and estrogen levels in men.

Next: This side effect can last longer than most people think.

Slowed reaction time

A closeup view of marijuana

Driving while high is not a good idea. | Bruce Bennett/Getty Images

  • Marijuana use can impair visual perception and motor speed for up to 28 days. 

Driving while high may seem like an obvious no, but impaired reaction time can last much longer than the high. “Visual perception and motor speed may be impaired not only while you smoke, but for up to 28 days afterward,” Marina Goldman, an addiction expert from University of Pennsylvania’s Addiction Treatment Center, told Philadelphia magazine. Slowed reaction time means that an oncoming vehicle can pose a greater danger; there could be a delay in perception time and appropriate reaction time.

Next: You need to know how marijuana edibles affect people differently.

Exposure to dangerous potencies

View of marijuana cupcakes for sale

Marijuana in edible form is very potent. | Alejandro Pagni/Getty Images

  • Marijuana has been increasing in potency — an edible tends to have a potency 10 times higher than a joint.

Today, marijuana products are much stronger than they used to be. Edible products tend to have a potency that is up to 10 times higher than that of a traditional joint, according to Steven Wright, a pain and addiction medicine specialist in Denver. Wright told USA Today that since edibles’ effects take up to an hour to set in — unlike joints, which reach the brain in just seconds — people end up consuming far more than they intended, which can cause more harm than the drug in its traditional form.

Next: You don’t always get the munchies.

Loss of appetite

a man refusing to eat a hamburger

This hamburger is missing something | iStock.com

  • Some frequent users lose their appetite when sober.

Everyone knows marijuana can trigger a case of the munchies, but some users complain they find their appetite disappears when they aren’t using the drug.

“I find that I don’t have much of an appetite any more unless I am stoned,” wrote Reddit user oz24. “[T]hinking about eating sober gave me nausea. [Probably] the worst part of all the side effects,” echoed user newmilwaukee.

Scientists who study the relationship between marijuana and appetite have discovered that a component of the drug appears to activate hormones that produce hunger, but it’s not clear what effect that might have on a person’s desire to eat when they weren’t high. A separate study found that people who smoked weed at least three times per week were skinnier than people who didn’t use marijuana, but why that is the case isn’t clear.

Next: Science says the relationship between marijuana use and paranoia isn’t a myth. 


marijuana plants

Marijuana plants | ROBYN BECK/AFP/Getty Images

  • People are more likely to experience paranoid thoughts after ingesting THC.

Tales of pot-induced paranoia aren’t unusual. “I smoked weed for about 6-7 years and eventually had to quit entirely because I became SUPER anxious, paranoid and self-conscious,” one Reddit user recounted. “[A]fter about 3/4 years of semi heavy use the high just changed now it just sends me loopy with bouts of anxiety and paranoia and just completely over thinking every aspect of my life until I can put a negative spin on it,” wrote blue_skies.

Science says the relationship between marijuana use and paranoia isn’t a myth. A 121-person study conducted at the University of Oxford found that people were more likely to experience paranoid thoughts after ingesting THC, the active ingredient in cannabis, than those who took a placebo. The drug also triggered negative thoughts about the self and lowered mood.

“There’s certainly evidence that if you use cannabis — particularly when you’re young — and you use it a lot, that this can put you at risk for later problems,” professor Daniel Freeman, who led the study, told WebMD. But paranoia isn’t an inevitable side effect of smoking weed, he added. “[I]f you have greater confidence in yourself, you improve your self-esteem, and if you try not to worry or ruminate about potential threats in the world … then the effects of the THC should hopefully be less capable of inducing paranoia.”

Next: Marijuana itself has never caused a fatal overdose, but …

Really bad decision making

Take it slow with marijuana use, especially edibles| Frederic J. Brown/AFP/Getty Images

  • Marijuana has never caused a fatal, toxic overdose, but does lead to potentially deadly choices.

While marijuana isn’t the only substance to help cause bad decision making, it highlights the importance of self-control and responsibility.

Medical experts and the Drug Enforcement Agency agree that marijuana has never caused a fatal, toxic overdose. However, there have been a few reports of excessive marijuana use leading to other fatal decisions, as was the case in March 2014 when a 19-year-old college student jumped off of a balcony after ingesting five times the recommended amount of marijuana.

Check out The Cheat Sheet on Facebook!

More Articles About:   , ,  

More from The Cheat Sheet