Cannabidiol, which is commonly referred to as CBD, is a relatively new drug that has been gaining popularity for its wide variety of uses and dosage forms. Many people claim that taking these products helps them sleep better, relieve their pain, and/or anxiety. It can be found readily available in lozenges, chewable gummies, sublingual tablets, and oil tinctures. However, due the lack of available information on these products, it is unsure if the medication is entirely safe for use especially when taken with other medications. To understand the potential interactions it may have with other medications, it is important to understand how it is metabolized, or in other words, is broken down in the body.
CBD is not actually active when ingested, it is activated by a certain enzyme (CYP2C19) which can be found primarily in liver cells. This enzyme then activates the drug. Afterwards, the drug must be inactivated prior to removing it via 2 different enzymes: CYP3A4 & UDT-glucuronosyltransferase.
There are many other drugs that are also broken down by the same enzymes. Some drugs can further stop the enzyme from working whereas other drugs might cause some enzymes to work even faster. This can cause less or more of the drug to be broken down respectively. Infact, CBD is considered to be a “potent inhibitor” of the enzyme CYP2C19.2 This means that when given with other drugs that are also broken down by the same enzyme, CBD may stop the other drugs from being taken in, hence hinder them from working. Some common drugs that are also metabolized by CYP2C19 include Prilosec, Nexium, Clopidogrel, and escitalopram. Therefore, taking them with CBD products could potentially alter their efficacy or prevent them from becoming active.
Other interactions may occur due to giving CBD with medications that have the similar effects. CBD is known to have sedative properties, which means patients taking it may feel drowsy. When giving it with medications such as benzodiazepines (ie. lorazepam, alprazolam) it can further exacerbate the side effects of the drug and lead to an unwanted increase in sedation.
Prior to taking CBD products, make sure to speak with your health care provider to help identify any potential interactions with your current medication regimen.
Pharm D Candidate 2022
Temple University School of Pharmacy
1. Gaston T, Bebin M, Cutter G, et al. Interactions between cannabidiol and commonly used antiepileptic drugs, Epilepsia. 2017;58(9),1586-1592. doi: 10.1111/epi.13852
2. Jjiang R, Yamaori S, et al. Cannabidiol Is a Potent Inhibitor of the Catalytic Activity of Cytochrome P450 2C19, J-Stage. 2013; 28(4), 332-338. doi: 10.2133/dmpk.dmpk-12-rg-129