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But many people still don’t really know what CBD is. Is it marijuana? Is it legal? Does it actually work? Is it safe?
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Consumers concerned about content and the accuracy of CBD products, which are not regulated by the Food and Drug Administration, can look for certification from independent lab testing or by scanning a QR code on product packaging.
There is no standardized dosage of CBD. Some retailers may have enough knowledge to make a recommendation for first-timers. There are also online resources – like this dosage calculator.
While 67% of U.S. adults support marijuana legalization, public knowledge about cannabis is low. A third of Americans think hemp and marijuana are the same thing, according to the National Institutes of Health, and many people still search Google to find out whether cannabidiol – a cannabis derivative known as CBD – will get them high, as marijuana does.
Hemp, marijuana and CBD are all related, but they differ in significant ways. Here’s what you need to know about their legality, effects and potential health benefits.
While the terms “CBD tincture” and “CBD oil” are often used interchangeably, the two are actually different. Tinctures are made by soaking cannabis in alcohol, while oils are made by suspending CBD in a carrier oil, like olive or coconut oil.
Brandon McFadden receives funding from U.S. Department of Agriculture.
The defining difference between hemp and marijuana is their psychoactive component: tetrahydrocannabinol, or THC. Hemp has 0.3% or less THC, meaning hemp-derived products don’t contain enough THC to create the “high” traditionally associated with marijuana.
The hemp industry, increasingly referred to as ‘Big Weed,’ is working to make CBD much more than a purported medication and is developing it in the US market as a food supplement that is widely used. Charlotte’s Web™ is an extract of hemp that has been widely touted as an option for treating seizures as well as a range of other medical conditions.9 The cultivar used by the Stanley Brothers is advertised to have a high-CBD content, which was specifically cultivated for a young epileptic patient named Charlotte.10 This case is instructive as to the claims made by the Stanley Brothers Social Enterprises, LLC, on various websites that implied their products were treatment for depression, cancer, diabetes and other conditions. On October 31, 2017, the FDA, Division of Pharmaceutical Quality Operations IV, issued a warning letter to Joel Stanley, CEO, Stanley Brothers Social Enterprises to correct the claims that the products are drugs and intended to diagnose, cure, mitigate, treat or prevent disease.11 In addition to being new drugs, the products were misbranded. The company has now modified their claims and provided disclaimer statements.12 On the same date, the FDA issued similar letters concerning misbranding of CBD to That’s Natural! Marketing & Consulting, Pueblo, CO12; Natural Alchemist, El Dorado Hills, CA13; and Greenroads Health, Pembroke Pines, FL.14 The City of Denver has established rules that apply to all CBD products sold or manufactured in the city.15 This is a step forward to protect consumers from contaminated CBD or CBD from uncertain origin and improper preparation.
All physicians must be aware of the impact, not only of THC, but of CBD on treatment and prescribing of pharmaceuticals to CBD consumers. The advertisements of over-the-counter CBD product as pure, as miracle treatments for a plethora of diseases and as fully legal to sell are blatantly false. The recent approval of Epidiolex ® for Lennox-Gastaut Syndrome, and Dravet Syndrome is the sole FDA approval of a CBD as a pharmaceutical. The efficacy of CBD for the many other proposed therapeutic uses has to be proven with legitimate scientific controlled studies. The companies that are advocating for CBD as a generally available health supplement are ignoring the Controlled Substances Act and the likely contamination with THC. CBD remains with a Schedule 1 classification and may place consumers, with no knowledge of the contents of the products, at risk. In a recent address at Institute of Cannabis Research, Dr. Di Marzo stated that the only effect of THC is to make a consumer high; thus, the CBD is the phytocannabinoid with the greatest current possibility to be useful as a medicine. Pharmaceutical preparations of CBD may ultimately be useful; however, current motivation appears to be the financial reward to the CBD industry rather than the health and well-being of the consumer.
CBD as a ‘Medicine’
A 2017 study looking at market share of products by a Cannabis investment group finds CBD is being used to replace traditional pharmaceuticals. The top conditions being treated included anxiety (67%), insomnia (60%), joint pain and inflammation (52%) and depression (43%). Respondents preferred CBD derived from cannabis to CBD derived from industrial hemp and only 9% of respondents indicated using hemp-derived CBD exclusively.20 The preference for CBD from Cannabis is significant because, without purification, the CBD extracted from Cannabis will, most likely, contain a much higher percentage of THC than does CBD from hemp.
An exception is Epidiolex ® . Epidiolex ® is a pure CBD liquid formulation that is produced by GW Pharmaceuticals in the UK.16 In June 2018 this CBD formulation was approved by the FDA for the treatment of two rare, severe forms of epilepsy (Lennox-Gastaut Syndrome and Dravet Syndrome.) GW Pharmaceuticals has received a number of patents that apply to the Epidiolex ® which has a purity of at least 98% (w/w) CBD and THC is less than 0.15% (w/w) at a dose of 10 mg/kg/day.17 As is appropriate for a medicine, the Epidiolex ® is of known purity and concentration and the efficacy has been evaluated by studies approved by the FDA. These patients will be under the care of a physician that will monitor and determine efficacy of the treatment. Epidiolex ® is also being evaluated as treatment for other conditions. This scientific approach to providing a medicine is in distinct contrast to the products being produced in many Colorado fields and barns by growers with no knowledge of quality control, extraction processes, contents, and quality of the final product, or the efficacy of the final product. The question is how aggressively GW Pharmaceuticals will address patent protection actions?
The focus of this article is CBD extracted from hemp which is generally defined as Cannabis sativa with a total THC less than 0.3% dry weight in leaves and buds. I emphasize that the only distinction between marijuana and hemp is the concentration of THC. A quick calculation for illustrative purposes shows that when hemp containing 0.3% THC and 5.0% CBD is subject to extraction the final product will contain THC as about 6% of the CBD, since the THC and CBD are removed in an essentially similar manner. The extracted product may contain other cannabinoids, residual solvents, oils from the plant, herbicides or pesticides and other organic molecules. The significant point is that an extract of hemp that is not purified and monitored will certainly contain some concentration of THC. Effective January 13, 2017, the Drug Enforcement Agency (DEA) created a new controlled substances code number (7350) for marijuana extracts.7 The DEA ruling is very clear that extracts of “any plant of the genus Cannabis, other than the separated resin” are included in Code 7350 in Schedule I of the CSA. This clearly includes extracts of hemp, which is a variety of the Cannabis plant; the US Court of Appeals for the 9 th Circuit Court denied a request by petitioners to review the DEA final rule.8 The DEA also notes there is no way to fully separate the THC from the CBD in extracts from the hemp. As a result, the CBD extracted from hemp remains a Schedule I substance.