With tens of millions of people using CBD, there is an increased risk of CBD drug interactions. Cannabidiol inhibits the CYP450 family of enzymes and impacts their ability to metabolize medication and other substances. When used with certain types of drugs, CBD could increase or decrease the medication’s effectiveness. It is of particular concern when using sedatives and blood thinners.
A Gallup poll from August 2019 stated that 14% of American adults admit using a CBD product. The highest prevalence is within the 18-29-year-old bracket; 20% of people in this age group take cannabidiol. Although the market is growing at a remarkable pace, it still has plenty of room to expand further. The same Gallup poll showed that 35% of U.S. adults were unfamiliar with the compound.
With so many people using it in this nation alone, the lack of guidelines in the industry is concerning. The FDA does not approve CBD (barring Epidiolex), and there is no industry regulation in place. As a result, low-grade CBD products flood the market. Some of them contain pesticides and heavy metals.
Users may endure side effects even if they use high-quality products. Knowledge of CBD oil drug interactions is nowhere near universal amongst the general public. If you use a prescription medication, this article is for you! It is also worth reading if you regularly use an OTC drug.
How CBD Interacts with Drugs and Medication
Cannabidiol is commonly used to manage symptoms of conditions such as anxiety, stress, depression, and chronic pain. In 2018, the World Health Organization (WHO) stated that the compound had a good safety profile.
A study by Iffland and Grotenhermen, published in Cannabis and Cannabinoid Research, looked at whether CBD was safe. Published in June 2017, the study concluded that CBD’s favorable safety profile was appropriate. However, it also said that researchers needed to examine crucial toxicological parameters.
However, there is no question that CBD oil and drug interactions are a real issue. The compound is a potent inhibitor of Cytochrome P450 (CYP450) enzymes. When you consume any substance, your body must metabolize it (break it down). While drug metabolism happens throughout the body, the liver does most of the work.
The CYP450 family of enzymes converts foreign substances, so they are removed from the body. Certain medications impact CYP450, by either increasing or decreasing the rate of drug metabolism in the body. The CYP450 enzymes metabolize approximately 60% of the medications currently on the market.
Meet the Family
The CYP450 family metabolizes many cannabinoids. It is CYP3A4 that performs this task. Alas, CBD interferes with this specific enzyme, as does THC. The CYP2C19 enzyme also metabolizes CBD, but not THC. CYP3A4 metabolizes an estimated 25% of all drugs. CBD also inhibits CYP2D6, which metabolizes antidepressants.
When you take cannabidiol while also on one of the medications metabolized by the CYP450 family, you are entering CBD and drug interactions territory. As CBD inhibits the enzymes, the CYP450 family isn’t as effective when trying to break down drugs in your system. If you use a drug that inhibits CYP3A4, your body won’t process the CBD as effectively.
You may end up with too much or too little of the prescribed medication in your system if you use it with CBD. This process can have dire consequences, as we outline below.
When in doubt, fall back on ‘the grapefruit rule.’ This methodology states that grapefruit potentially impairs how your body absorbs specific drugs. It primarily affects allergy, blood pressure, and cholesterol medications. Like CBD, grapefruit inhibits the CYP450 family of enzymes. While prescription drugs come with a grapefruit warning, CBD users don’t get the same protection.
It appears as if low doses of CBD don’t have a massive effect on how your body processes other drugs. At the time of writing, however, there isn’t ample research available to outline what a ‘safe’ dose is in this context.
Drugs That Interact with CBD Oil
Logically, it is wise to avoid any medicine that you can’t take with grapefruit. The following CBD drug interactions list is a long way from exhaustive. We recommend performing more detailed research to see if your medication is affected.
CBD and Drugs That Increase Risk of Bleeding
There is a link between drugs that thin blood, such as warfarin, and CBD. Research also shows that drugs that carry a heightened risk of bleeding, like ibuprofen, also interact with the compound.
A study by Grayson et al., published in Epilepsy & Behavioral Case Reports, investigated the link between CBD and Warfarin interaction. Published in 2018, the study concluded that there WAS an interaction between the two substances.
Overall, it seems as if the usage of CBD increasesthe effects of blood thinners and drugs with an added risk of bleeding. It is the same situation with other plant cannabinoids. We have much to learn about drug interactions between CBD and other pharmaceuticals.
CBD and Sedatives
While the relationship between the two is not known fully, physicians don’t recommend using CBD with sedatives. There is a risk that high doses of cannabinoids may lead to an undesired additive effect. Sedatives suppress the central nervous system and are often prescribed to treat anxiety and sleep disorders.
If you use sedatives and CBD together, you could experience a heightened effect. A study by Brown and Winterstein looked at the potential for drug interactions with CBD. Published in the Journal of Clinical Medicine in July 2019, the researchers concluded that CBD wasn’t a biologically inert compound.
Instead, it has a complex pharmacodynamic and pharmacokinetic profile similar to other medications. As a result, it could interact with other drugs. Therefore, it is not a good idea to mix CBD with a drug such as Xanax or Ambien. While this particular interaction may not have a direct negative effect, there is a chance it will increase the feeling of sedation.
CBD with Seizure Medication
CBD is linked with anti-epileptic benefits. The case of Charlotte Figi is arguably the most famous, but there are many other instances. Patients with conditions such as Dravet’s Syndrome can suffer hundreds of seizures each month. Charlotte received CBD from a plant renamed Charlotte’s Web and experienced a dramatic reduction in the frequency and intensity of her seizures.
Epilepsy drugs don’t work for at least one-third of people with the condition. As a result, there is a movement towards CBD and cannabis oil to treat it. The FDA has approved Epidiolex, a pharmaceutical drug with CBD, as the main active ingredient. However, there is a lack of evidence to suggest that CBD formulations work as well as cannabidiol from a cannabis or hemp plant.
CBD is likely the most active cannabinoid in marijuana when treating epilepsy. A study by Perucca, published in the Journal of Epilepsy Research, looked at the effects of cannabinoids on epilepsy. It determined that CBD was more productive as an epilepsy treatment than THC.
Anti-epileptic medication is one instance where a drug interaction is potentially useful. As the study by Bornheim et al. shows, CBD impairs the CYP450 enzyme family. As a result, drugs such as clobazam are likely more effective when used with CBD. However, you must still closely monitor the dosage. Make sure you speak to a physician first!
CBD and Chemotherapy Drugs
Patients who take CBD for cancer aim to manage symptoms such as nausea and vomiting associated with chemotherapy. Once again, it is best to look at the grapefruit rule. Almost 100 drugs interact with grapefruit and closely related juices such as tangelos and Seville oranges. Anticancer medications are on the list of drugs that possibly interact with CBD.
While you may believe that ‘anything’ is better than how you feel right now, please consult with a doctor before combining CBD with anticancer drugs.
What Drugs Should Not be Taken With CBD?
The following is a list of common drug types that use the Cytochrome P450 system. Again, it is not a complete list.
- Calcium Channel Blockers
- HIV antivirals
- Oral Hypoglycemic Agents
- Angiotensin II Blockers
- Immune Modulators
- HMG CoA Reductase Inhibitors
Consult a Doctor Regarding CBD Drug Interactions
No matter your condition, please do your research into drug interactions with CBD oil. It is best if you steer clear of cannabidiol if you currently use a medication metabolized by the CYP450 liver enzymes. If you are unsure, discuss the possibility of CBD interactions with a physician.
If you want to use cannabidiol, your doctor may adjust the dose of your other medications. Even though CBD is seemingly safe, there is a health risk if it is mixed with certain drugs. It is always advisable to err on the side of caution where your health is concerned.
Bottom Line on CBD Drug Interactions
CBD oil drug interactions are real, and they could affect you. Of course, there are other factors involved. For example, the timing of when you use CBD and other medication plays a role in any possible CBD drug interactions. By spacing out the doses, you reduce the liver’s workload. For example, you may reduce the risk of adverse effects by using your medication in the morning. Then, you can use CBD in the evening or at night.
Also, the method of consumption matters. CBD taken sublingually has a higher absorption rate than an edible, for instance. Incidentally, those who use CBD on their skin are least likely to experience any drug interactions. This is because the amount of cannabinoid absorbed and sent to the bloodstream is minimal in this instance.
When you ingest CBD, it must go through the gastrointestinal system, which decreases its bioavailability. Vaporizing cannabidiol has a higher absorption rate than any other method barring intravenous consumption. If you have any questions or concerns, please talk to your doctor before proceeding with CBD when already on other medications.