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What Pharmacists Need to Know About CBD?


An Introduction

Over the past several years, CBD has become a focus for research and legislation. CBD is one of the most popular types of cannabinoids, and has been shown to reduce inflammation, convulsions, anxiety, and nausea, , along with reducing the number and severity of certain epileptic seizures.

The projected retail sales for CBD products are expected to reach $1.9 billion by 2020. Legislation regarding CBD products is evolving slowly, in contrast to the studies past and present streamlining research on hemp-derivatives, including CBD, and speeding up the development of new drugs.

CBD derived from any cannabis source was previously a Schedule I controlled substance; therefore, research of CBD was limited due to the Controlled Substances Act (CSA) formally making it illegal to cultivate, possess, sale, and distribute CBD.

The 2014 Farm Bill was subsequently signed into law, which differentiated industrial hemp from marijuana, and authorized industrial hemp research by institutions of higher education or departments of agriculture in states where hemp cultivation was legalized. Later, the 2018 Farm Bill removed hemp from the CSA, paving the way for the legal cultivation, possession, sale, and distribution of hemp.

Hemp is regarded by the federal government as cannabis containing no more than 0.3% THC, which means that federally legal CBD, which must be derived from hemp or other lawful source, shall contain no more than 0.3% THC.

CBD, when derived from marijuana, or “all parts” of the cannabis plant, remains a Schedule I substance. The CBD manufacturers we selected derive CBD only from hemp plants and are THC-free. Even in this case, there is still possibly of an issue with drug testing due to CBD reactivity and false-positives.

The 2018 Farm Bill also explicitly preserved the FDA’s authority to regulate any products containing hemp-derivatives under the U.S. Federal Food, Drug, and Cosmetic Act (FDCA). FDA has not approved the use of CBD as a dietary supplement or food additive.

With greater patient access to CBD, pharmacists will need to be prepared to address potential drug interactions to help patients use these products safely. Since 2016, the FDA has issued numerous warning letters instructing various manufacturers to halt production of OTC CBD products, due to significant discrepancies existing between the tested contents of products and strengths listed on the product labels. As some products were found to contain no trace of CBD compounds during quality testing, widespread mislabeling can easily occur in the absence of strict FDA enforcement.

Furthermore, there is no standard production method among CBD manufacturers, which can lead to impurities being introduced into products. Therefore, microbiological, pesticide, and heavy metal contamination can lead to harmful effects. These risks can be mitigated by patients obtaining CBD products from reliable sources, such as pharmacies that have screened vendors as trusted CBD suppliers. That is why we carefully screened NCPA CDB Source vendors and do our own random product testing at an independent lab.

Regarding interactions, in vitro studies have illustrated multiple potential drug interactions for CBD. The lack of standardized products somewhat limits the ability to make definitive statements from available research, but there is evidence that CBD is an inhibitor of many CYP450 enzymes including 2D6, 3A4, and 3A5, as well as a potent p-glycoprotein (P-gp) inhibitor. Since these are common enzymes of drug metabolism, and with the widespread adoption of CBD oil use by chronic pain patients, there exists a high potential for drug-drug interactions and safety concerns.

Research also suggests CBD use enhances the effect of opiates, and exhibits other interactions with barbiturates, fluoxetine, sedatives, and antihistamines, as well as having synergistic effects with alcohol. More detail of this is available in the education materials.

Community pharmacists are well positioned to intervene clinically at the forefront of this health culture trend. While OTC products appear safe to many consumers, FDA warning letters to numerous manufacturers suggest otherwise.

Pharmacists are patient advocates who protect against adverse outcomes. It is important for pharmacists to stay abreast of ongoing research developments regarding CBD products. Staying current with emerging literature and evidence-based research on this topic is the best way for pharmacists to ensure they are continuing to provide the most competent and comprehensive care for their patients.

Sourced from the article Cannabidiol Products’ Impact on Pharmacist-Provided Medication Management


Dillion Barbour, PharmD; Ece Okarlton, PharmD; Bryce T. Platt, PharmD; Rebecca W. Chater, RPh, MPH, FAPhA; and Adam Moss, PharmD Candidate