Blood clot blocking a blood vessel - 3D illustration

Can CBD Oil Thin Your Blood?

Given what it can do, it’s no wonder people are concerned about the possible side effects of CBD oil. Researchers and scientists are steadily building knowledge about CBD and other cannabinoids to find out how and to what extent they relieve pain, help our stress responses, regulate sleep, and more. 

More is being discovered about CBD and cannabinoids all the time, which is why questions about its side effects keep coming up. We do know that it can interact with some medications and have dire consequences for people with heart issues and other risk factors.

Does CBD oil act as a blood thinner by itself? How does CBD oil interact with anticoagulants like warfarin? Should you stop taking CBD before an operation? Find out these answers and more in this comprehensive guide to CBD oil and blood thinners.

The Basics Of Blood Thinners

Arteries, veins, and capillaries are the three kinds of blood vessels that transport blood around the human body. The average speed of blood is between 3 and 4 miles per hour - pretty fast considering the average height of an adult human male is 176.5 centimeters, or 0.001 miles.

Blood vessels with artery and vein internal structure comparison vector illustration.

When your body needs to stem blood flow - for instance, when you get a cut or an injury - it makes cells called platelets that group together to create blood clots. You might have heard of clotting issues like Deep Vein Thrombosis and the buildup of plaque on artery walls that can lead to pulmonary embolisms and other serious health problems.

Blood thinners are meant to address and prevent these issues. Blood thinners don’t actually make your blood thinner or dilute it in any way. They work by stopping the formation of blood clots and preventing existing blood clots from getting any bigger. People who have had heart attacks or a stroke are prescribed blood thinners to prevent future ones.

The human body needs to be able to thin blood and create clots based on new conditions. According to one study, cannabidiol (CBD) “inhibits CYP2C19, increasing levels of the active metabolite of clobazam threefold.” The researchers also add that smoking marijuana could have “serious interactions with drugs like warfarin,” warfarin being a common anticoagulant sold under the name Coumadin among others.

What this basically indicates is that there is very likely a possibility that CBD and other hemp extracts can inhibit the inhibitors, essentially wrecking the efficacy of blood thinners like warfarin. But what about people who aren’t on blood thinners? Should they be worried about taking CBD oil?

CBD Oil & Thinning Blood

The danger with combining CBD oil and blood-thinning medications is that both can act as blood thinners, thinning your blood more than your doctor intended. That would seem to indicate that CBD oil has anticoagulant effects on its own.

A study found that cannabis sativa and the cannabinoids tetrahydrocannabinol (THC) and cannabinol (CBN) “display anticoagulant activity” when introduced in an animal specimen. CBD wasn’t singled out with the other two extracts. So do CBD products have the same effect as the two cannabis plant extractions mentioned in that study?

The widely accepted answer is that yes, CBD oil has some effect on the thinness of your blood. Harvard Health Publishing, for example, has said that CBD can “increase the level of blood thinning and other medicines in your blood by competing for the liver enzymes that break down these drugs.”

They do go on to mention that grapefruit is known to have a similar effect. The National Health Service (NHS) in the UK instructs readers taking warfarin to avoid grapefruit juice but also mentions some different blood-thinning medications that present less of a risk when grapefruit juice is present in the body and competing with medication in the liver’s enzyme system.

If we follow the logic backward, it appears reasonable to draw the conclusion that anyone worried about a negative drug interaction, bleeding complication, suffering from heart disease, having a history of strokes, or otherwise concerned or vulnerable to potential complications from CBD products should avoid taking them without discussing them with a medical professional first.

Reduce Risk With Trusted Brands

Follow medical advice from a trusted doctor or qualified professional when you start a CBD oil regimen. If you’ve agreed that CBD is a viable treatment option or that you don’t have risk factors that counter its potential health benefits, you have to make sure you find the right provider that doesn’t include harmful additives in their products.

Whether you’re using edibles, full-spectrum CBD, terpenes, cannabis extract, topicals, hemp oil, or a tincture, make sure you find one with a list of all active ingredients. In case you’re looking for a worst-case scenario, the FDA put out a warning in 2018 that some synthetic cannabinoid products were found to be laced with an anticoagulant called brodifacoum that’s typically found in rat poison.

Since these were described as being sold at gas stations and convenience stores, it’s highly likely they weren’t coming from the most reputable suppliers out there. Do your research and make sure you know exactly what you’re taking before you start taking CBD oil or any similar product. The FDA doesn’t regulate supplements, so shopping around is paramount.

Is CBD Oil An Operation Risk?

Some doctors ask patients to stop taking CBD oil 48 hours or more before a scheduled procedure while others don’t think it’s a serious risk. Doubtless, trained medical professionals know what to look for in individuals so they can make an informed decision about what’s best. It might be comforting to know that, in most cases at least, a history of CBD consumption won’t automatically prevent doctors from getting people the treatment they need.

An example case study from 2017 describes a 44-year old caucasian male who had been having seizures starting when he was 27. The seizures followed a stroke that followed cardiac surgery. The mechanical valve put in place during the cardiac surgery and the nature of his seizures made the 44-year old a bad candidate for surgery, so his doctors opted to refer him to the University of Alabama’s CBD program. 

He was taking the blood thinner warfarin in addition to a few other medications to keep his International Normalized Ratio (INR) in line with what was healthy. According to the case study, the patient’s primary care physician slowly lowered his dose of warfarin in tandem with the increase in CBD administered. The final recommendation of the case study is to use INR monitoring when CBD treatment is being administered alongside prescription drugs like warfarin or heparin.

This is a great illustration of an apparently common method of managing the potential risk of CBD’s antiplatelet effects. At the end of the case study, the 44-year old was taking a dose of warfarin that was about 30% lower than when he started and continuing to have CBD administered. 

So even if the research about CBDs’ effects on blood thinning and interactions with blood thinners is still far from complete, it’s clear medical professionals are being precautious. It’s best to trust the advice of a trusted medical professional to make sure you’re taking CBD as safely as possible.

Does CBD Oil Lower Your Blood Pressure?

The studies are pretty much across the board on this question. One promising experiment from 2017 indicated that “acute administration of CBD reduces resting blood pressure and the blood pressure increase to stress in humans, associated with an increased heart rate,” which basically means that the 9 participants in the study experienced a drop in their resting blood pressure after a single dose of cannabidiol.

What does that mean for people who have to bring their blood pressure over time, can a regimen of CBD oil accomplish the task? That’s where the research gets a bit less promising. One study from 2020 remarks that CBD “has not affected blood pressure in hypertensive animals.” The same study mentions that most incidents of hypotensive action (low blood pressure) occurred mainly during stress conditions. 

Other studies seem to point to some positive results on blood pressure when participants take CBD in moments of stress. However, the evidence either doesn’t support or isn’t conclusive enough to support the idea that CBD is a viable treatment option for lower blood pressure over the long term. You might think that thinner blood automatically creates lower blood pressure, but the two concepts aren’t related.

The beating of your heart creates blood pressure while clotting is meant to stop internal and external bleeding. Adding platelets to the bloodstream doesn’t impact blood pressure. Even when platelets completely block the bloodstream like they do in thrombosis, blood pressure doesn’t change.

But that acute drop in blood pressure could possibly cause problems in certain individuals. If you have problems with your blood pressure being too low in general, it might not be a great idea to consume CBD oil and similar products that source from the hemp plant.

Is CBD Oil Safe?

Ok, so if CBD oil can possibly interact with prescription medications and cause blood to thin and blood pressure to drop following consumption, is it safe to take? Only your doctor can tell you for sure whether it’s a smart treatment option for you. Many have used it to successfully treat epilepsy, anxiety, narcolepsy, and insomnia. By and large, it appears that it is “a promising candidate of both somatic and psychiatric disorders.”

Dropping essential oil into glass bottle on blurred green background.

Many people take CBD oil without any issue. It isn’t psychoactive and there is no indication that it has any addictive qualities. For the majority of people, taking CBD oil from a reputable source where you can see all the active ingredients and none are harmful shouldn’t be a problem.

It’s not as intense as medical marijuana and is available in some places where Mary Jane is not. Many people have used it for pain management or just to relax. People respond differently to these products depending on their individual body chemistry and the context in which they take them.

Some healthcare professionals view CBD oil as a safe alternative to opioids and other prescription treatments for anxiety and sleep disorders. By and large, it is safe. But you should still consult a doctor or another healthcare provider to determine whether you can and are likely to benefit from CBD oil.

Does CBD Oil Thin Blood More Than Other Cannabinoids?

Marijuana as a whole and CBD oil as a part of the whole have both been found to have anticoagulant properties. The best course of action is to avoid hemp-based edible or consumable products if you’re taking heart medication and can’t reach a doctor to get a decision on whether or not CBD oil, edibles, topicals, or even THC products would be dangerous for you to take.

As far as whether CBD oil possesses a blood-thinning capability superior to other extracts from hemp, there’s not much research available on the topic. Out of an abundance of caution, don’t assume that any one product will have less of a blood-thinning effect than another one unless a doctor has told you so.

Despite the indications that CBD oil and other hemp-based products interact badly with blood thinners and could cause your body’s clot-producing ability to fall below where it should be, anecdotal information on the internet seems to indicate that some doctors don’t think it’s a big risk.

Still, an in-person doctor would know best about your health condition and what kinds of factors will have an impact on it. Ask a medical professional before you start taking CBD oil if you’re on blood thinners or at risk for stroke or heart attack. There’s a chance they’ll say it’s fine, but if they say it isn’t you should follow their instructions.

Conclusion

CBD oil has had many positive effects on users’ stress levels and allowed them to sleep more soundly during the night. Doctors have administered CBD oil for epilepsy, narcolepsy, and generalized anxiety disorders. It’s useful for relaxing without the psychoactive characteristics of marijuana or THC.

But marijuana and hemp-derived compounds have been found to interact poorly with blood thinners. For people who take these sorts of prescription medications, anything sourced from the hemp plant could cause some problems.

The danger of taking CBD oil on top of blood thinners is that your blood will become “too thin,” in essence, both of them perform the same function in terms of platelets. So you’d essentially be taking too much of what you need to stay healthy, which can be as disastrous as not staying healthy at all.

Still, the way doctors have balanced CBD administration with steadily decreasing amounts of drugs like warfarin gives some hope that medical professionals will one day know for sure how to organize CBD regimens for people who have had strokes and heart attacks to make sure they can safely take CBD. They’ve already been successful in at least one case study.

For now, users of CBD should check with their doctors to make sure it’s safe for them to start or continue using the product. It’s worth an ask even if you think you’re low-risk. The better prepared and informed you are before you start your CBD regimen, the more beneficial it will be for you in the long run.

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