In November 2017, the World Health Organization (WHO) released a report that brought global attention to the safety profile of CBD1. Another report followed in 2018 that explained clearly that CBD has no addictive or abuse potential on its users. The report elaborated that CBD does not have any effect on the intracranial self-stimulation2.
The WHO also found that CBD does not contain any adverse health effects and is well tolerated in both humans and animals.
While surpassing all supplements in terms of high sales in the United States, according to Mayo Clinic, it is always recommended to check with your doctor before starting on its regimen3. It is true that CBD is safe; however, when you’re taking other medications, it is always prudent to know if CBD might cause some kind of drug interaction with your current pills.
With all the fuss around CBD products comes one recurring question: Does topical CBD interact with medications? Can CBD lotion actually make you dizzy?
If you’re someone who uses CBD topicals and takes prescription or over-the-counter medications at the same time; then, this is one article that can clarify it all for you!
What is Drug Interaction?
Before analyzing whether topical CBD products may interact negatively with your drugs causing possible harmful side effects, you have to understand what a drug interaction is.
Drug interactions happen when you take more than one medication or supplement at a time. According to the FDA, drug interactions can make a drug less effective, cause unexpected side effects, or increase the action of a particular drug. These interactions may be harmful on the patient4.
Drug interactions fall into three different categories, which include:
When two or more drugs interact with one another leading to unexpected side effects. For example, if you mix a sedative and with allergies medicine, you might end up with slowed-down reactions and reflexes putting you at danger if you were driving a car.
Drug/Food or Beverage Interactions
When drugs interact with food or beverages.
Taking a benzodiazepine (like Valium), for example, and drinking alcohol can cause side effects like confusion, dizziness, sedation, loss of consciousness, and (in severe instances) death. Also, taking blood thinners and eating parsley can make your blood too thin and cause intensive bleeding if you had a cut.
When certain existing medical conditions make certain drugs potentially harmful.
If you have hypertension, high blood pressure, for example, and take a decongestant or pain medication such as ibuprofen, you could experience an adverse reaction.
Table of Contents
CBD and the Cytochrome P450 Enzyme System
Research shows that CBD can inhibit the cytochrome P450 enzyme system, which is found within the liver and responsible for metabolizing compounds that could be toxic including over 60% of any drugs that have been taken. Such a power over this pathway will prevent other medications from accessing the enzymes, which could lead to a build up of medications in the system. As a result, it may take a certain medication much longer to start doing its effect and the accumulated dose may be harmful to the body instead of being curative. Even a small amount of CBD can trigger such an effect5.
To establish dosing sizes of particular medications, doctors calculate the average time it would take a drug to pass through the cytochrome P450 enzyme system and get metabolized. The result is a series of unwanted side effects.
Keep in mind that ANY drug metabolized by the cytochrome p450 system contains the potential to interact with CBD.
For example, CBD cream may interacts with warfarin. Due to the same interaction with the P450 enzyme pathways, doses of warfarin may need to be decreased in order to prevent any harmful effects. If you are on blood thinners, you need to talk to your doctor6.
For a complete list of these drugs, click here. Some of the most common include:
- Immune Modulators
Will CBD cause a negative reaction if you’re taking a drug that’s metabolized by the cytochrome P450 system? Nothing is 100% sure; but it is best to be on the safe side and consult with your doctor or pharmacist before using CBD.
Will Topical CBD Products Cause a Drug Interaction?
CBD topicals are everyone's favorite for several reasons.
First, they provide localized relief. If you suffer from a sore knee, painful wrist, or an achy back, a CBD cream can target the painful area and soothe it. All you will have to do is simply rub a CBD topical on your sore spot and let the non-psychoactive cannabinoid work its magic.
Second, CBD topicals work quickly to provide the relief you need. They get absorbed by the skin fast. The skin contains its own endocannabinoid system.
Unlike CBD oils or edibles, CBD topicals are not digested in the body and absorbed by the bloodstream. So, a CBD salve, cream, balm, or lotion is not expected to cause any possible drug interaction.
By not entering the digestive system and getting digested, it doesn’t make its way through the liver or interact with the cytochrome P450 system. So, CBD creams, salves, balms, and lotions should NOT cause a drug interaction.
CBD Topicals COULD Cause an Allergic Reaction, Though…
It is true that CBD topicals are not supposed to cause any drug interaction; however, they may cause an allergic reaction.
When a topical rubbed on the wrist suddenly causes the skin to become very hot and turn bright red, it is an allergic reaction. Such a reaction might go on its own without any treatment. However, if applied again, it may happen again and start getting worse with time and repetitive applications.
So, if you notice unwanted effects upon using a CBD cream on your skin, this is not the right cream for you.
An allergic reaction is NOT a drug interaction.
When using CBD topicals you should always check the ingredients. If you don’t notice anything on the label that you may be allergic to, you may try to apply the cream on your skin. But, you need to start with a small amount for a test-drive, before applying liberally.
Some are nor aware of any possible allergy they may have until they try a new product that triggers some kind of a reaction. So, keep your attention of testing any new cream before making it a daily routine.
Do Transdermal CBD Patches Cause a Drug Interaction?
What about transdermal CBD patches? Here is the story about patched: they are not the same as the CBD topicals. Transdermal CBD patches are designed to enter the bloodstream; so, logically, one would assume that they could cause a drug interaction.
But, with the lack of valid scientific evidence to prove otherwise, it isn’t likely that this topical method of CBD application would cause a drug interaction.
Why not, though?
While a CBD transdermal patch will cause CBD to enter the bloodstream, it doesn’t cause CBD to be absorbed by the liver.
This is because transdermal patches are direct to the bloodstream and do not get metabolized. This type of CBD delivery method bypasses the digestive tract and liver altogether.
Dr. Noel Palmer is one of the cannabis industry’s most well-known transdermal patch developers and an award-winning laboratory scientist specializing in plant properties.
When asked about the benefits of transdermal patches, he had the following to say7:
“The reason why you use a patch is it’s direct to the bloodstream, it’s a slow timed release, and it’s a fairly benign way to administer a drug for someone who may be averse to taking a pill, to vaporizing, to those kinds of things.
“Especially with THC, when ingested, it goes through your liver, and all of a sudden you get these THC metabolites floating around in the body that are totally different pharmacologically. When you eat [cannabis], you get a spike of 11-Hydroxy-THC – which is actually very strong and might be stronger than the Delta-9. This may be why people are having these kinds of psychedelic experiences when they eat cannabis.
“But with the patch, in theory, you don’t get that because you’re going direct to the bloodstream, so you’re not going to get these kinds of secondary metabolites that you would when you ingest.”
Because transdermal CBD doesn’t go through the liver where the cytochrome P450 enzyme system is found, there’s likely little chance that the transdermal application of CBD will cause an adverse drug interaction.
You should always check with your doctor before using any type of CBD products. Especially if you’re currently taking other medications.
Topicals like CBD balms, creams, lotions, and salves shouldn’t cause a drug interaction as they’re not absorbed by the liver. And while there isn’t sufficient research (yet) to back it up, transdermal CBD patches shouldn’t either as they’re absorbed directly into the bloodstream through the skin and bypass the liver completely.
Don’t forget to check with your doctor before starting on any new regimen.
1W., P., M., & D. (2017). CANNABIDOIL (CBD) (Rep.). Retrieved January 28, 2021, from World Health Organization website: https://www.who.int/medicines/access/controlled-substances/5.2_CBD.pdf
2W., P., D., D., & J. (2018). CANNABIDIOL (CBD) Critical Review Report (Rep.). Retrieved January 28, 2021, from World Health Organization website: https://www.who.int/medicines/access/controlled-substances/CannabidiolCriticalReview.pdf
3Balzer, D. (2019, August 22). Mayo Clinic Minute: Is CBD safe to use? Retrieved January 28, 2021, from https://newsnetwork.mayoclinic.org/discussion/mayo-clinic-minute-is-cbd-safe-to-use/
4Center for Drug Evaluation and Research. (2013, September 25). Drug Interactions: What You Should Know. Retrieved January 28, 2021, from https://www.fda.gov/drugs/resources-you-drugs/drug-interactions-what-you-should-know
7Lland, R. (2020, July 28). What are THC, CBD, and other cannabis-derived transdermal patches? Retrieved January 28, 2021, from https://www.leafly.com/news/strains-products/what-are-marijuana-transdermal-patches