Adults only (18+)

Can Weed Cause a Heart Attack?

The relationship between cannabis use and heart health has become an increasingly discussed topic, especially as more people turn to weed for recreational or medical reasons. A commonly asked question is whether using weed can lead to a heart attack. While cannabis may be viewed by many as a relatively low-risk substance, particularly when compared to tobacco or alcohol, it can have real physiological effects that impact the cardiovascular system. Understanding how weed interacts with the heart and circulatory system is important for anyone with existing heart conditions, or for those concerned about their overall cardiovascular risk.

How Cannabis Affects the Heart

Cannabis contains active compounds such as THC and CBD, but it is THC that causes the psychoactive effects most commonly associated with being high. When THC enters the bloodstream, it binds to cannabinoid receptors in the brain and body, including those found in the heart and blood vessels. This can lead to temporary changes in heart rate, blood pressure and vascular tone. In many users, cannabis increases the heart rate by 20 to 50 beats per minute shortly after consumption. It can also cause blood vessels to dilate, leading to a drop in blood pressure. These changes may not be noticeable or harmful to a healthy person, but for someone with an underlying heart condition, they could pose a greater risk.

Possible Links to Heart Attack Risk

Research has explored whether cannabis use might trigger a heart attack, especially in the hours following use. Some studies suggest that the risk of a heart attack may be slightly elevated in the first hour after smoking cannabis due to the increase in heart rate and the added demand on the heart. These effects may be more pronounced in older adults or in individuals with known heart disease, high blood pressure or high cholesterol. The combination of cannabis use with other risk factors such as tobacco smoking or sedentary lifestyle may further compound the likelihood of a cardiac event. However, the overall risk remains relatively low for most people, and more research is still needed to fully understand the long-term cardiovascular effects of cannabis.

Differences Between Smoking and Other Methods

The method of cannabis consumption can influence its effects on the heart. Smoking weed introduces not only THC but also combustion by-products, which may include harmful substances similar to those found in tobacco smoke. This can irritate the lungs and cardiovascular system, potentially raising the risk of heart problems over time. Vaping or consuming edibles may reduce exposure to combustion-related toxins, but they still introduce THC into the body and carry similar effects on heart rate and blood pressure. It is also worth noting that edibles can have a delayed onset, which sometimes leads users to take higher doses unintentionally, increasing physiological stress.

Cannabis and Individuals with Existing Heart Conditions

For people with diagnosed cardiovascular issues such as angina, heart rhythm disorders or a history of heart attacks, the use of cannabis should be approached with caution. Any substance that increases heart rate or alters blood pressure may destabilise the heart's function. Some cardiologists recommend avoiding cannabis altogether in these cases, or at the very least, consulting a medical professional before use. It is also important to consider drug interactions if someone is taking prescription heart medication, as THC can interfere with the metabolism of certain drugs and alter their effectiveness or side effects.

What the Experts Say

While many cannabis users report no negative impact on their heart health, medical experts tend to err on the side of caution. Health authorities such as the British Heart Foundation advise people with heart disease or risk factors to speak to a healthcare provider before using cannabis. They note that although the risk of a heart attack linked to cannabis is not high in healthy individuals, the evidence is still developing and the impact can vary widely depending on the individual. Cardiologists are particularly concerned about the effects of cannabis on blood pressure, irregular heart rhythms and clotting, all of which can influence cardiovascular health in the short and long term.

Conclusion

Cannabis can affect the heart by increasing heart rate and altering blood pressure, which may raise the risk of a heart attack in vulnerable individuals. While the overall risk is considered low for most healthy users, those with existing heart conditions or multiple risk factors should be especially cautious. Smoking weed may pose additional cardiovascular risks due to the inhalation of combustion products. As with any substance that affects the body’s systems, it is important to make informed decisions and seek medical advice if there are concerns about heart health. Weed may not directly cause heart attacks in most users, but it can contribute to conditions that increase cardiovascular strain.