Cannabis Science

Is Smoking Weed Bad For Your Heart?

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Stoners may notice their heart beating faster when they’re high. Therefore it’s natural to wonder about the various ways weed may affect your heart. Is smoking weed bad for your heart? Here’s what we know about the relationship between heart health and weed. 

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How Does Weed Affect Your Heart?

According to a 2014 article called Cardiovascular Consequences of Marijuana Use, smoking weed can cause your heart to beat faster and a mild increase in blood pressure too. What’s interesting is that the study states that this is dose-dependent. That means higher amounts of weed are associated with a higher heart rate.

Harvard Health also mentioned that using weed affects the heart by dilating blood vessels and making the heart pump harder. 

Is this dangerous?

 Well, the 2014 article mentioned a large cohort study that did not find any link between weed use and cardiovascular disease hospitalization or mortality. In addition to that, Harvard Health, marijuana, “does not pose a significant threat to people who have minimal cardiovascular risk, it should be a red flag for anyone with a history of heart disease.”

Therefore, if you already have heart problems, marijuana can be dangerous. According to the 2014 article, “acute effects of marijuana use include a decrease of the time until the onset of chest pain in patients with angina pectoris”. 

Just to clarify, angina pectoris, according to John Hopkins Medicine, angina pectoris or just angina, are recurring chest pains or discomfort. Angina occurs when the heart doesn’t get enough blood or oxygen. In addition to that, angina could be a symptom of coronary artery disease (CAD). 

Therefore the 2014 article is saying that weed can cause chest pains due to angina occurring more frequently. 

In addition to affecting angina, Harvard Health, weed can increase the risk of atrial fibrillation, the most common heart rhythm disorder. Weed is also associated with an increased risk of atrial fibrillation or ischemic stroke. The risk increases right after marijuana use. One review says, “Cannabis use has been reported to increase risk of ischemic stroke, particularly in the healthy young patients.”

Can Pot Give You a Heart Attack?


According to Harvard Health, using weed increases your risk of heart attack. The article says  “The risk of heart attack is several times higher in the hour after smoking marijuana than it would be normally”.Harvard Health also says that smoking weed may increase the long-term death rate among heart attack survivors.

There also seems to be an increase in people hospitalized for heart attack who also have cannabis use disorder. says, “4.1% of patients hospitalized for heart attacks also had cannabis use disorder, and the proportion nearly tripled from 2.4% in 2007 to 6.7% in 2018.”

It’s important to note that this study is not showing a direct cause of weed and heart attacks. As puts it, the study didn’t account for the role of other substances like tobacco, cocaine, or alcohol. All of these symptoms can have detrimental effects on the heart. 

In addition to that, the Centers for Disease Control and Prevention (CDC) says that research that links marijuana to heart attacks (and strokes) are based on reports from people who smoked marijuana. Therefore, there could be something in the smoke itself that causes the problem as opposed to marijuana and its other components. 

The CDC said that smoking marijuana delivers many of the same harmful compounds found in tobacco smoke. These substances are linked to cardiovascular issues. The CDC says, “It is hard to separate the effects of marijuana chemicals on the cardiovascular system from those caused by the irritants and other chemicals that are present in the smoke.” Therefore, more research is needed. 

Does Weed Help Heart Problems?

Even though weed is used to fix many other health issues, heart problems may not be one of them. 

There are some upsides to using cannabis. Larry Allen, MD, medical director of the advanced heart failure program at the University of Colorado Anschutz Medical Campus told Web MD some of the upsides. 

Allen does say that regular use of cannabis has “more downsides than upsides”. 

However, Allen says patients report cannabis helps with chronic swelling in the belly or legs. These are heart failure symptoms. In addition to that, cannabis helps heart failure victims with nausea and appetite. CBD, according to a study, can also reduce heart rate and blood pressure. 

At the same time, weed can make heart problems worse. Web MD says that weed can make heart failure worse by causing:

  • Narrow arteries 
  • A rise in blood pressure
  • Worsening of uneven heartbeat
  • Lower pumping abilities 

In addition to that, Harvard Health says weed may negatively affect your heart by interacting with medication used to prevent or treat heart disease. 


Is smoking weed bad for your heart? It definitely can be. If you don’t have pre-existing heart problems, you may be okay, however, that’s not certain. More research is necessary. Even though weed can also alleviate some of the issues associated with heart disease, it’s best to avoid weed if you have heart issues. Weed can definitely make heart issues worse.


About Trevann

Trevann is Stoner Rotation’s Jamaica-based lead writer for the Science section of our cannabis blog. She graduated with honors receiving her Bachelor of Science degree in Molecular Biology from the University of West Indies, Mona. For the last three years, she has covered some of the biggest questions around cannabis and health underpinned with research from supporting studies, medical journals and scholarly articles. Got something on your mind? You can reach her at [email protected].