Marijuana’s Effects on the Heart

Marijuana is a common recreation drug, which is the most common recreational drug used in the United States and perhaps the world. In 1997, a survey of 12th graders found that about 50% of them had reported smoking marijuana at least once. Despite the public ‘s perception that marijuana is a benign drug with minimal side effects, there is a growing body of evidence to suggest that marijuana has both a neuropsychiatric and cardiac effects.

This article will discuss the potential cardiac side effects of marijuana.

Marijuana is an inhaled substance, which has many effects on the heart and blood. It has been shown to create a increased coagulation (clotting) in the blood, which increases the aggregation of platelets. The body has to have a balance between clotting and bleeding, that is, it has different mechanisms to maintain a balance where the blood will not clot too easily, but on the other hand, will also not bleed to easily. Marijuana shifts this balance more to the clotting aspect versus the bleeding aspect. Hence, this leads to an increased likelihood of a stroke in the brain (clot that originated in the heart). It also increases the possibility of a small clot forming in the heart, which could also then travel to the arteries surrounding the heart and cause a heart attack.

Marijuana has been shown to induce both an increase or more likely a decrease in the heart rate of an individual user. This is because marijuana has a biphasic effect on the autonomic nervous system (that regulates the heart rate and blood pressure of the body). It has been shown in research studies that at low doses, it induces a sympathetic response in the body, which leads to an increase in blood pressure and heart rate. However, at a higher dose, it can induce a decrease in heart rate and blood pressure. One may see the former effect present in someone who complains of palpitations or feeling nervous. In the latter effect, an individual user may complain of feeling tired and lightheaded (. The slow heart rate may even lead to what is termed heart block, which is when the electricity in the heart begins to malfunction. At this point, some of these individuals may require a long term pacemaker.

In conclusion, marijuana is a frequently used recreational drug and although many feel that it is harmless and benign, there is more evidence that marijuana may increase an individual risk for heart attacks, stroke, and heart block.