Cannabidiol (CBD) is an active ingredient across Cannabis species.  CBD has a chemical structure that is almost identical to delta-9 tetrahydrocannabinoid (THC). However, these two kissing cousin compounds have no shared pharmacology or effects. While THC is known to be intoxicating, CBD is not.  All 50 states have laws legalizing CBD with varying degrees of restriction. The federal government still lists CBD in the same class as marijuana (a Schedule 1 drug- or having no accepted medical use and potential for abuse) but does not consistently enforce against the sales of CBD. In December 2015, the FDA made it possible to allow research on CBD. 

Is CBD Legal?

Currently, many people obtain CBD online without a medical cannabis license. The government’s position on CBD is confusing and depends in part on whether the CBD comes from hemp or marijuana. Hemp is a crop (of the Cannabis genus) that has traditionally been grown for fiber and may or may not contain any cannabinoid compounds. If it does, the THC content by definition of the US Federal government must be less than 0.3% (by weight). Marijuana, on the other hand, is Cannabis that contains over 0.3% THC. The legality of CBD is expected to change, as the Farm Bill made the hemp crop legal and will make it more difficult to prohibit CBD sales. 

Until the FDA makes a ruling about CBD sold as supplements, sales are technically illegal, even if you purchase it from a doctor’s office. Products that have been derived from legal cannabis in the State of California, and may be dominant in CBD content (very little THC), can be purchased at licensed cannabis retail outlets.  Despite the murky legal status of CBD, it is always a good idea to talk with your healthcare provider about any and all supplements that you take.  There is no legal risk in speaking with your doctor about CBD or Cannabis.

Sourcing CBD

A whole-plant extract of hemp likely contains some amount of  THC, although some companies claim to be isolating the CBD (or removing the THC). Because of the lack of regulation, it is difficult to know exactly what you are purchasing. If you are planning to purchase a hemp-based product, look for one made from hemp grown in the United States from a manufacturer that conducts quality control testing.

Certificates of analysis may be available on their website, or you can request this.  This analysis will confirm that there are no pesticides, microbial or fungal contamination of the product, and should provide you with the information on how many milligrams of CBD is in a dose. However, the FDA has warned that the labels are not always accurate. California has not mandated quality control testing for hemp-based products, while other adult-use cannabis must pass stringent quality control testing

Health Benefits of CBD

CBD is being touted as a treatment for a wide variety of health issues. The strongest scientific evidence for CBD is for the most untreatable childhood epilepsies known as Dravet and Lennox-Gastaut syndromes. Recently the FDA approved the first-ever cannabis-derived medicine for these two conditions, Epidiolex, which is an isolated form of CBD and not a whole plant extract (contains no THC). This drug has not yet been approved by the FDA to treat any other conditions. 

Some CBD manufacturers have come under FDA scrutiny for indefensible claims such as:  “CBD is a cure-all for cancer” (which it is not) or will “stimulate hair growth” (no proof of this). We definitely need more research on what CBD may be useful for, other than seizure. For instance, managing anxiety, insomnia, or mild inflammatory pain (some research exists for these indications).  

CBD is not a very potent compound, meaning that high doses are needed to produce pharmacologic effects (higher doses than required with THC, which is a very potent molecule). CBD is not typically sedating at the doses found in many hemp-based products, but research has shown that high dose (around 350 mg) may cause sedation.  There is a dose-related risk of drug interactions with CBD and you should talk with your doctor about this potential. Despite some claims, CBD is not converted to THC in the body.  However, if a hemp-based product contains any amount of THC this could show up in a urine or blood drug screening test.

Remember that CBD may not have much effect at a low dose (it has rarely been studied clinically at under 75 mg). Because of all of the hype around CBD, it is possible that the craze about it is just a “placebo effect” (due to the belief in the product, not because the product itself is effective). If you decide to try CBD, talk with your doctor — particularly if you are on other prescription medications, to ensure it won’t affect the metabolism of those drugs.

Until we know much more about what CBD is good for, the best that can be said is that it appears to be non-toxic or has a good safety profile, at least in healthy individuals. Alternatively, it could be the very low amounts of THC  found in hemp-based products that boost the therapeutic benefit. The combination of all of the many compounds found in botanical medicines (whole plant extracts), used for thousands of years across cultures, resulting in a synergy that adds up to provide effects. More research, such as that occurring through the Center for Medical Cannabis Research at UCSD will help to clear up some of the haze around CBD!

Michelle Sexton, ND
Dr. Sexton is an Assistant Adjunct Professor for the University of California, San Diego Department of Anesthesia.
Dr. Sexton’s NIH-funded pre and post-doctoral research was on the topic of cannabinoids and their roles in neuro-inflammation and neuro-degeneration. She is a member of the International Cannabinoid Research Society, the International Association of Cannabinoid Medicine and the Society of Cannabis Clinicians. She maintains a medical practice in San Diego, CA and she sees patients for integrative neurology, chronic inflammation, chronic pain, autoimmune diseases and cancer support.


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