US Pharm. 2019;44(3):13-14.

A Compound From the Cannabis Plant

Cannabidiol (CBD) is one of the many active ingredients derived from the plant species Cannabis sativa. There are several strains of the Cannabis sativa plant, with the two most common being marijuana and hemp. Industrial hemp has a high percentage of the phytocannabinoid CBD and a very low concentration (less than 0.3%) of THC (tetrahydrocannabinol). THC is the psychoactive, mood-altering component associated with the “high” of marijuana. CBD is not associated with psychoactive effects and does not have the same risk of abuse or dependency. CBD is growing in popularity and was most recently approved by the FDA for very specific medical uses.

Legal Status of CBD

Though federal law prohibits the cultivation, sale, and use of marijuana, several states and territories have legalized marijuana for medical purposes and recreational use. Some states only approved the use of CBD alone for medicinal purposes. 

In December 2018, the Hemp Farming Act was signed into law in the United States. This act removed the Schedule I controlled-substance classification from hemp (THC less than 0.3%) and classified it as an agricultural product. CBD products derived from the industrial hemp plant are now available in all 50 states in many different formulations, and they are touted to treat a wide range of conditions from pain and inflammation to depression and epilepsy. CBD is available in oil, tincture, vaporization liquid, and pill forms and can be purchased both in stores and online. The Hemp Farming Act does not apply to products and formulations derived from the marijuana plant, which is still considered a Schedule I controlled substance by the federal government.

Safety

The most common side effects reported with the use of CBD include appetite alteration, sleepiness, gastrointestinal disturbances/diarrhea, weight changes, fatigue, and nausea. Uncommon or rare adverse events include thrombocytopenia (low blood platelets), respiratory infections, and alteration of the liver enzymes.

CBD can inhibit the body’s ability to metabolize certain drugs, leading to an overall increase in processing times and higher-than-expected drug levels in the blood. Interestingly, CBD oil is not alone in its effect on drug metabolism. Grapefruit, watercress, St. John’s wort, and goldenseal all have a similar impact on drug metabolism. If you are taking a medication affected by CBD, you should consult with your doctor to make sure that it is safe for you to supplement with CBD or to discuss adjusting the dosage on your medications so that you can use both products safely. 

FDA-Approved Formulations for Epilepsy

On June 25, 2018, the FDA approved Epidiolex (cannabidiol), a highly purified pharmaceutical CBD formulation, as a treatment for seizures associated with Dravet syndrome and Lennox-Gastaut syndrome in patients aged 2 years and older. Epidolex is the first FDA-approved treatment for Dravet and is considered a significant advancement for this patient population. The exact mechanism of action for the treatment of seizure is unknown.

Experimental and Anecdotal Uses

A growing body of evidence suggests that CBD has properties that can improve overall health and manage specific conditions. CBD has anti-inflammatory properties, which may be beneficial for arthritis and other pain. It is also shown to have effects on brain chemistry, which may be helpful for those suffering from depression, anxiety, or insomnia. Finally, early human studies suggest CBD could play a role in treating opioid addiction and other types of substance abuse.

With all of the promising therapeutic applications for CBD, caution should be exercised when using CBD for medical therapy. Since CBD is considered a supplement and not a drug, it is not held up to the same level of scrutiny when it comes to purity and dosing, or in proving efficacy and safety. It is unclear which doses and which dosage forms work for best for each condition, making dosing recommendations a guess, at best.

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