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Surprising Side Effects of Smoking Marijuana

Although pot has its benefits, it's not without side effects.
FACT CHECKED BY Emilia Paluszek

The public acceptance of marijuana has skyrocketed in recent years, and increased legalization means that more people have access to recreational marijuana than ever. Although pot has its benefits, it's not without side effects, some you may never have considered. Read on to find out more—and to ensure your health and the health of others, don't miss these Sure Signs You've Already Had COVID.


Lung Irritation

Unlike tobacco, marijuana use has not been found to raise the risk of lung cancer. But it still involves inhaling smoke, which can be hard on your lungs. "Marijuana smoke irritates the lungs, and people who smoke marijuana frequently can have the same breathing problems as those who smoke tobacco," says the NIDA. You may experience coughing, increased mucus, wheezing or chest tightness. 


Increased Heart Attack Risk

closeup man's chest heart attack

Experts say that THC, the main ingredient in marijuana, can increase the heart rate—by 20 to 50 beats in a minute, lasting for several hours. According to Harvard Medical School, the risk of a heart attack is greater in the hours after smoking marijuana than it is normally. And a study published in the journal Cell last month found that frequent marijuana users are more likely to have a first heart attack before the age of 50. Researchers think THC may cause inflammation in blood vessels, raising that risk.


Stomach Upset

Young woman suffers, writhes in abdominal pain lying on couch in living room at home interior

Marijuana is occasionally prescribed to relieve nausea, but it can also cause stomach problems itself. For people with cannabinoid hyperemesis syndrome (CHS), using marijuana can lead to stomach pain, nausea, and vomiting, sometimes severe. And it's surprisingly common—experts estimate 2.7 million Americans experience the condition. According to the Cleveland Clinic, you have a higher risk of developing CHS if you use marijuana at least once a week, and if you've used marijuana since adolescence.


Neurological Issues

woman puts hands on head, stressed, busy at work

Last February in the journal Stroke, the American Heart Association warned doctors that pot's effects on the brain are unclear, and they should have "balanced" discussions with patients about potential risks. A review of studies published last January in the journal Addiction found that THC, the main psychoactive compound in marijuana, can impair the brain's executive functions, including planning, organizing, solving problems, making decisions, and regulating emotions. 


Mental Health Issues

Shot of a young woman suffering from depression in her bedroom

Marijuana has a long reputation as a relaxant. But taking too much of it can have the opposite effect, causing anxiety, paranoia, and even panic attacks, says the Centers for Disease Control and Prevention. "Several studies have linked marijuana use to increased risk for psychiatric disorders, including psychosis (schizophrenia), depression, anxiety, and substance use disorders, but whether and to what extent it actually causes these conditions is not always easy to determine," says the National Institutes of Health. And to protect your life and the lives of others, don't visit any of these 35 Places You're Most Likely to Catch COVID.

Michael Martin
Michael Martin is a New York City-based writer and editor. Read more about Michael
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