More than three million Americans take Eliquis (apixaban), a blood thinning medication prescribed for treating blood clots and preventing clotting in people with conditions like atrial fibrillation and peripheral artery disease. But many people wonder, should you use cannabis while taking Eliquis?
Eliquis is one of the most prescribed blood thinners on the market today, so many people taking it are also taking other medications and supplements, including cannabis. But is it safe to use cannabis with Eliquis? Here’s what research reveals about the way these two substances interact – and whether it’s wise to use cannabis while taking this new type of blood thinning drug.
What is Eliquis?
Eliquis is one of several drugs used to inhibit proteins that cause blood to clot. While clotting is a vital process for closing wounds and protecting them, blood clots that form in the veins and arteries can cause strokes, circulation problems and even death. The class of “blood thinners” also includes older drugs like warfarin (coumadin) and heparin, but they target different factors that affect clotting.
Like warfarin and heparin, Eliquis is used to prevent blood clots from forming in a variety of conditions including:
- Deep vein thrombosis, which can cause clotting in the legs and other parts of the body
- Atrial fibrillation, a condition in which the heart beats irregularly
- Peripheral artery disease, which causes poor blood circulation in the limbs
- Stroke
Eliquis has a number of side effects, mainly excessive bruising and the risk of serious bleeding due to the blood’s inability to clot. That’s why Eliquis users are told to avoid situations that could cause bruising or bleeding, like working with sharp utensils or playing contact sports.
The risk of bleeding while taking Eliquis increases when it’s used with a long list of other common medications including aspirin, non-steroidal anti-inflammatories (NSAIDs) and herbal supplements including St. John’s Wort. These medications can either cause bleeding on their own, like aspirin, or affect the way the body processes Eliquis. And while research is limited, some studies suggest that cannabis compounds like THC and CBD might have similar effects, especially when used in large amounts.
How Does Cannabis Interact with Eliquis?
Eliquis belongs to a new category of blood thinners called Factor Xa inhibitors. These medications are considered safer and more effective than older anticoagulants like warfarin and heparin. Eliquis blocks Factor Xa, which produces the clotting protein thrombin, while warfarin and similar drugs are vitamin K antagonists, which means that they block Vitamin K’s ability to release clotting proteins. Warfarin and other vitamin K antagonists require regular INR (international normalized ratio) testing to check for blood levels of the drug, but Eliquis doesn’t require regular INR tests.
Because Eliquis is a relatively new drug, much of the research on the interactions between cannabis and blood thinners has focused on warfarin. But although Eliquis and warfarin target different clotting factors in the blood, they’re metabolized by the liver on the same pathways. That gives researchers some insight into the pptential effects of cannabis on Eliquis.
The liver metabolizes drugs and other external toxins through a set of enzymes called cytochrome p450, or CYP450. The cytochrome P450 system accounts for 70 to 80 percent of the enzymes involved in drug clearance, making it the most important system for drug metabolism.
Within the CYP450 system, specific enzyme groups act on these chemicals to make them available to the body. But when these substances compete for space on the same pathways they can either boost the activity of enzymes in that pathway, so that chemicals are metabolized quickly, or inhibit it, which slows processing and intensifies the effects of a drug or other substance.
THC and CBD, the most prevalent compounds in cannabis, are processed by the same CYP450 enzyme pathways as Eliquis, warfarin and other blood thinners. This means that cannabis products can affect the way these drugs are metabolized and made available to the body.
Recent research on the effect of cannabis on anticoagulant drugs indicates that cannabis inhibits the activity of the relevant CYP450 enzymes, so that they’re less efficient at metabolizing the drugs. When that happens, blood levels of the drug will rise and its effects on the body are magnified. One study found that high doses of CBD can inhibit the processing of warfarin on shared CYP450 pathways. For one test subject, that led to markedly elevated levels of warfarin, which could cause serious side effects.
Although research on the effects of cannabis specifically on Eliquis are limited, the same CYP450 pathways are involved. So, when Eliquis is taken concurrently with CBD and/or THC, blood levels of Eliquis could potentially rise. And when Eliquis levels rise excessively, blood clotting may be compromised. That could cause outcomes ranging from frequent bloody noses all the way on up to a potentially fatal event, such as a hemorrhagic stroke or heart attack.
Should You Take Cannabis While Taking Eliquis?
With a few exceptions involving very large amounts of CBD and other cannabis products, there has been no reporting of clinical cases of excess anticoagulation due to cannabis use while on Eliquis. Along with that, patients using cannabis in relatively low amounts while taking anticoagulants don’t report any clinically significant effects.
But a highly elevated Eliquis level can lead to serious consequences, so it’s important to discuss using cannabis with your prescribing physician and follow their recommendations for staying safe while using Eliquis.