CBD and Drug Interactions: What to Know and Be Careful Of

CBD has become wildly popular in the past few years, and with good reason: Some scientific evidence and a slew of anecdotal data have indicated CBD may be able to help people reduce a variety of physical and emotional challenges.

Research is still attempting to understand how CBD works and what it’s various benefits are. On that front, initial results are positive, as numerous studies and a report by the World Health Organization have noted that CBD is relatively safe, well-tolerated in humans and shows low potential for abuse.

However, like any substance, CBD is not completely risk-free, and some studies have found that CBD does contain the potential for negative drug interactions.

CBD and Your Liver

Every living human has a functioning liver. The primary responsibility of your liver is essentially to act as a giant filter, cleansing the blood which comes from your digestive tract before sending that blood back into your circulatory system.

CBD, like any other substance your body ingests, is ultimately broken down by your liver. As part of this job, your liver produces a series of enzymes that are used in removing your blood of toxins and breaking down chemicals. This is where CBD can create problems for your body.

Your liver produces many enzymes. One such example is a series of enzymes that are part of the cytochrome P450 family.

Cytochrome P450 Enzymes

The responsibility of these enzymes is to work to filter compounds that your body ingests in order to break them down so they are eliminated by the body. There are a series of specific enzymes in this family that deal with different foreign medications.

Having a properly functioning liver is vitally important when it comes to taking prescription medication. The reason for this is simple: When medications are created, they are done so in a way that compensates for the normal functioning of these critical enzymes. As such, medications are crafted in a very specific way. If the functioning of your liver enzymes is altered, you may end up consuming more or less of a medication than the medication was designed for. This may result in less than designed effects, or a series of negative consequences and debilitating side effects.

The Problem with CBD and Liver Enzymes

Numerous studies have found that CBD inhibits the creation of these liver enzymes. For example, CBD has been found to inhibit CYP34A and CYP2D6, which metabolizes many anti-depressants.

Specific studies on CBD have revealed similar interactions. For example:

• A study in 2012 found that individuals taking the drug Warfarin (a common medication to treat or prevent blood clots) revealed that individuals taking Warfarin and CBD showed increased levels of Warfarin in their bloodstream. This can damage a person’s ability to form blood clots beyond safe measures.
• A 2015 study found that children taking clobazam (a drug taken to treat epilepsy) and CBD showed increased clobazam levels.

Another small study found that 10% of all participants who were taking CBD developed “dangerously high liver enzymes,” and had to discontinue their CBD use as a result.

Broadly speaking, as many as 60% of medications currently available (over the counter medications or prescription medication) are metabolized via P450 enzymes. A Huffington Post article on the subject notes that this is not a hard and fast rule. Furthermore, a variety of factors could strengthen or weaken CBD’s impact on your P450 enzymes. This includes the between consumption of CBD and medication, the form in which you consume the CBD, and your metabolism.

The Grapefruit Warning

Broadly speaking, there is no hard and fast rule about which drugs may give you a problem and which will not. However, there is a rough guideline: The Grapefruit Warning.

Many medications have broad warnings against consuming the medication in question and grapefruit (and, occasionally, other citrus fruits). This is because grapefruits have chemical compounds called furanocoumarins. Furanocoumarins bind to P450 enzymes and dramatically hinder their ability to metabolize other medications. As a result, you wind up having higher levels of the medication in question then you were intended to, and this can put you in grave danger.

The impact of CBD and grapefruit on your P450 enzymes are not identical, but there are similarities. As such, if you take a medication that has a grapefruit warning like this, it is unquestionably safer for you to avoid taking CBD.

The Most Important Thing You Can Do

Talk with your doctor or another medical professional before starting CBD.

As noted above, initial research indicates that CBD appears to be relatively safe for most people. However, if you take any other medication, or if you have liver problems, you may find yourself in a situation where your body is ingesting too much, or too little, of a medication. It goes without saying that this is a situation that should be avoided, lest you suffer any number of physical or emotional challenges.

As such, the safest thing you can do before starting CBD is to have a long conversation with your doctor. Your doctor should know whether or not you are on any medication that may lead to a negative interaction with CBD, or if taking the CBD is an unnecessary medical risk for you. Furthermore, the research on this field is rapidly evolving, and your doctor is likely to know whether or not there is no research that indicates other potential problems or negative interactions with CBD.

Fortunately, generally speaking, CBD consumption is safe. However, you should always talk with your doctor before starting any regular medication or supplement – even if it’s something as simple as taking a daily vitamin. The same certainly goes for taking CBD.