While you might assume that cannabis has a calming effect on the heart, the psychoactive drug can actually cause the heart to work harder and faster, potentially leading to serious cardiovascular complications. 

According to the CDC, much more research is needed to understand how cannabis affects the heart.

CDC. Cannabis and Heart Health. February 15, 2024.

However, growing evidence consistently links cannabis use to increased risk of stroke, heart disease, and other vascular diseases.

CDC. Cannabis Health Effects. February 16, 2024.

Effects of cannabis on the heart

Research has found, for example, that frequent cannabis use is linked to increased heart rate and elevated blood pressure.

Subramaniam VN, Menezes AR, DeSchutter A, et al. The Cardiovascular Effects of Marijuana: Are the Potential Adverse Effects Worth the High? Missouri Medicine. 2019;116(2):146–153.

According to Jasdeep Dalawari, MD, an interventional cardiologist and the Regional Chief Medical Officer of VitalSolution, an Ingenovis Health company, these issues increase the amount of oxygen the heart needs to function. 

Over time, this can lead to endothelial dysfunction, increased arterial stiffness, and inflammation, says Sam Setareh, MD, MS, Director of Clinical Cardiology and Cardiovascular Performance at Beverly Hills Cardiovascular. These conditions also put people at risk of a heart attack and stroke. 

Evidence suggests that the way a person uses cannabis influences how the drug affects the heart.

Chayasirisobhon S. Mechanisms of Action and Pharmacokinetics of Cannabis. Permanente Journal. 2020;25:19.200.

“The overall cardiovascular risks remain similar regardless of the method of administration,” Dr. Setareh adds.

In general, smaller doses and infrequent use are best, according to Dr. Dalawari. That said, even tiny amounts can be risky, especially in people with underlying cardiovascular conditions.

Risks of heart attack or stroke are higher with chronic use, but even trying cannabis once can precipitate a cardiovascular event, Dr. Setareh notes. “Both frequency and dosage are critical factors, with higher and more frequent use posing greater risks,” Dr. Setareh adds.