“Heart failure patients should know that while CBD has been touted as a wonder compound and seems to be in almost everything these days, it has never been shown to have any significant cardiovascular benefits in human studies,” says Scott Lundgren, DO, a transplant cardiologist at Nebraska Medicine in Omaha.
What Is CBD Oil?
CBD oil contains cannabidiol, an herbal liquid supplement made from the cannabis plant. It doesn’t have the same effect on the brain as THC, another compound found in cannabis that gives you a “high” when smoked or eaten, says Larry Allen, MD, associate division head for clinical affairs in cardiology at University of Colorado Anschutz Medical Campus.
“There are no known cardiovascular benefits for cannabis or cannabidiol, and there may even be some adverse effects, so people should not take these products and think that it will have positive effects on their cardiovascular health,” says Allen, who’s also co-author of the American Heart Association’s statement on all cannabis products.
In 2018, the FDA approved the first oral, purified CBD drug, Epidiolex, to treat seizures in two rare forms of epilepsy. Two synthetic versions of cannabidiol were later approved: dronabinol (Marinol, Syndros) for treatment of nausea during cancer chemotherapy and nabilone (Cesamet) to treat weight loss associated with AIDS.
Some of CBD’s proven benefits in other health conditions may be intriguing to people living with heart failure, Allen says.
“Does it stimulate your appetite? Yes. Do people gain weight if they take it? Possibly true. Patients with severe heart failure do have cachexia,” or severe weight loss and muscle wasting, he says. “One could argue that people with nausea, lack of appetite, or who are losing weight could think CBD would help them. People with heart failure have a fair amount of discomfort, including edema [swelling] and somatic or pain-related issues, so you could think CBD has a role.”
But there isn’t really any evidence to prove that it will relieve heart failure symptoms or be safe to use if you have heart failure, he adds.
What We Know About CBD
Some research suggests that CBD oil may improve some heart-related symptoms:
- A very small study conducted in 2017 in England found that CBD improved resting blood pressure and blood pressure spikes related to stress in people without heart conditions.
- Various studies in animals have shown that CBD could improve vasorelaxation, or opening of arteries for better blood flow, as well as reduce inflammation. A small clinical trial from Mexico studying CBD in people with heart failure hasn’t reported any results yet.
- A large study of more than 161,000 people hospitalized for heart failure who had used marijuana found that they had, on average, a lower risk of death and shorter hospital stays. But this doesn’t necessarily mean CBD oil would have the same benefit.
It’s illegal in the U.S. to market CBD by adding it to any food or calling it a dietary supplement. Also, although the FDA has approved a few CBD drugs to treat certain diseases, don’t expect CBD sold over the counter to be safe or beneficial for heart failure, Lundgren says.
“CBD oil may not have the same properties, and it can actually cause gastrointestinal distress like diarrhea or cause decreased appetite. CBD products can include unknown ingredients and may not be accurately labeled,” he says.
When you use CBD oil, your liver breaks it down. During this process, it could interfere with your medications for heart failure or other heart conditions. “CBD has known interactions with warfarin, certain statins, calcium channel blockers, beta-blockers, and nitrates. Just because a supplement is ‘natural’ doesn’t mean that it is safe,” Lundgren says.
CBD May Have Health Risks
CBD oil must be studied in randomized clinical trials on people, not animals, before it can be considered safe or effective for heart failure, Lundgren says. Until that happens, he advises against buying or using CBD. “There is some evidence that CBD can cause liver injury as well as lead to male infertility issues. When consumed with alcohol, individuals may experience increased drowsiness, which can lead to household injuries.”
If you have heart failure, you might feel like you’re taking control of your own care by trying herbal treatments that don’t require a prescription. To be safe, talk to your cardiologist first: Ask questions about CBD oil and make decisions together about using this or any other supplement, Allen says.
“CBD products cost money and can distract you from taking prescribed treatments for heart failure that are evidence-based. They could do indirect harm to people with heart failure. … We already have a half-dozen treatments for heart failure symptoms and to help you live longer.”