Cannabidiol has a long list of reported therapeutic properties and can be supportive of the body’s endocannabinoid system, but like anything else, it is important that you understand how it is metabolized and how it could impact your prescription medications.
Over 60% of prescription medications are metabolized by cytochrome P450 enzymes, the same enzymes that metabolize cannabidiol; thus the reason why it is referred to as a competitive inhibitor particularly when taken in large doses. During the metabolization process, cannabidiol can block other chemical compounds from being metabolized which can result in higher concentration levels of chemical constituents in the body. This can be either a positive or negative factor, depending on the compound, but it is something to take into consideration if you are taking medications that are also metabolized by the P450 enzyme and you want to add cannabidiol to your daily wellness routine.
Although it’s impossible to list all of the prescription medications that could be impacted by cannabidiol’s metabolization process, below is a list of drugs that are also metabolized by cytochrome P450 enzymes:
|· Steroids||· HMG CoA reductase inhibitors|
|· Calcium channel blockers||· Antihistamines|
|· Prokinetics||· HIV antivirals|
|· Immune modulators||· Benzodiazepines|
|· Anti-arrhythmics||· Antibiotics|
|· Anesthetics||· Antipsychotics|
|· Antidepressants||· Anti-epileptics|
|· Beta-blockers||· PPIs|
|· NSAIDs||· Angiotensin II blockers|
|· Oral hypoglycemic agents||· Sulfonylureas|
If you or someone close to you are taking prescription medications, particularly in higher doses, it is recommended that you talk with your health care provider or pharmacist to see if they see any potential risks.
If you are taking lifesaving medications, your blood levels should be monitored regularly so that dosing of your medications and cannabinoids can be adjusted appropriately and effectively.
Some important interactions you will want to pay particular attention to are anticoagulants, chemotherapy drugs, and epilepsy medications.
Cannabidiol may block the metabolization of anticoagulant medications like warfarin and coumadin which could increase plasma concentrations of these medications which can, in turn, increase the risk of bleeding.
Chemotherapy is administered in very high, precise doses with the intent of killing cancer cells. Cannabidiol may inhibit the metabolization of chemotherapy medications causing toxic concentration levels within the body.
It is worth noting; patients have been using cannabis to counteract the powerful side effects of chemotherapy for many years with very few documented accounts of adverse drug interactions. Could it be that whole plant synergies, rather than isolated cannabinoid compounds, are more effective in this scenario? Unfortunately, until cannabis becomes legal on a federal level and government-backed randomized double-blind-placebo-controlled clinical trials are conducted, we may not get a definitive answer to this question, but I digress.
Cannabidiol can elevate plasma levels and increase blood concentrations of clobazam and its active metabolite norclobazam. When considering cannabidiol as an adjunctive therapy patients should consult with their health care provider so that blood levels can be monitored. In many cases, patients may be able to reduce their dosage of traditional antiseizure medications.
The Bottom Line
When considering cannabidiol as a part of your treatment plan particularly if you are taking any of the prescribed drugs mentioned above, it is important to communicate with your health care provider so that proper monitoring can be done to achieve maximum results from the combined therapies.
- “New Study Finds CBD Interacts with Antiepileptic Drugs.” ECHO Connection, 30 Nov. 2017, echoconnection.org/new-study-finds-cbd-interacts-antiepileptic-drugs/
- Grayson, Leslie et al. “An interaction between warfarin and cannabidiol, a case report” Epilepsy & behavior case reports 9 10-11. 12 Oct. 2017, doi:10.1016/j.ebcr.2017.10.001
- Leinow, Leonard and Juliana Birnbaum. CBD A Patient’s Guide to Medicinal Cannabis. North Atlantic Books, 2017.
- Perucca, Emilio. “Cannabinoids in the Treatment of Epilepsy: Hard Evidence at Last?” Journal of epilepsy research 7,2 61-76. 31 Dec. 2017, doi:10.14581/jer.17012