A Clinicians’ Guide to CBD and Hemp Oils

Cannabidiol (CBD) oils are low tetrahydrocannabinol (THC) products derived from Cannabis sativa that have become very popular over the past few years. Patients report relief for a variety of conditions, particularly pain, without the intoxicating adverse effects of medical marijuana. In June 2018, the first CBD-based drug, Epidiolex, was approved by the US Food and Drug Administration for treatment of rare, severe epilepsy, further putting the spotlight on CBD and hemp oils. There is a growing body of preclinical and clinical evidence to support use of CBD oils for many conditions, suggesting its potential role as another option for treating challenging chronic pain or opioid addiction. Care must be taken when directing patients toward CBD products because there is little regulation, and studies have found inaccurate labeling of CBD and tetrahydrocannabinol quantities. This article provides an overview of the scientific work on cannabinoids, CBD, and hemp oil and the distinction between marijuana, hemp, and the different components of CBD and hemp oil products. We summarize the current legal status of CBD and hemp oils in the United States and provide a guide to identifying higher-quality products so that clinicians can advise their patients on the safest and most evidence-based formulations. This review is based on a PubMed search using the terms CBD, cannabidiol, hemp oil, and medical marijuana. Articles were screened for relevance, and those with the most up-to-date information were selected for inclusion.

One of the biggest challenges facing health care today is combating opioid abuse, with medical and non-medical overuse of opioids exacting a huge toll on society in recent years. Although there has been a larger focus on reducing opioid prescriptions and preventing non-medical use of opioids, there is an increasing interest in finding more treatment options for patients in pain, and the diverse field of integrative medicine has been finding an increasing role in this area. One promising area has been use of the plant Cannabis sativa, both in medical marijuana as well as hemp and cannabidiol (CBD) oils, with some evidence that access to medical marijuana is correlated with a decrease in opioid use, although there has been controversy about the risks and benefits of encouraging poorly regulated medical use of a known substance of abuse. Cannabidiol and hemp oils have become especially popular because of their low tetrahydrocannabinol (THC) levels, resulting in attributed medical benefits without the “high” of marijuana. However, clinicians have concerns about whether these treatment options are legal, safe, and effective and are largely unfamiliar with these products. Therefore, we provide an overview of the scientific work on cannabinoids, CBD, and hemp oil and clarify the distinction between marijuana, hemp, and the different components of CBD and hemp oil products so that clinicians may be able to direct their patients to the safest and most evidence-based products.

Cannabis sativa has long been utilized by human populations across the world for its therapeutic properties, from pain relief to treatment of epilepsy.10 Marijuana and hemp are 2 strains of the same plant, C sativa, with marijuana being cultivated over the years for its THC content and hemp for its myriad other uses including paper, clothing, and food.11 Despite considerable sociopolitical obstacles, scientific understanding of C sativa has progressed substantially in the past 30 years as the many active ingredients of the C sativa strains were isolated and major discoveries were made regarding the body’s own endogenous cannabinoids and the endocannabinoid system (ECS).

The chief ingredients of hemp oils are phytocannabinoids such as CBD and terpenoids such as BCP and limonene. However, there is a paucity of clinical research conducted on these important components because most research focuses on THC and CB1 receptors (the primary target of THC). Much less data are available on CBD, which works via a variety of complex mechanisms noted previously, and BCP, which works through the less-understood CB2 receptors. According to a recent systematic review on the medical uses of cannabinoids, there was moderate-quality evidence to support the use of cannabinoids for chronic pain and spasticity, and low-quality evidence to support use for nausea and vomiting due to chemotherapy, weight gain in HIV infection, sleep disorders, and Tourette syndrome. However, it is important to realize that most of the randomized controlled trials examined in this systematic review for each condition were of the 3 prescriptible THC drugs dronabinol, nabilone, and nabiximols; only 4 trials were found for CBD, and none for any of the other phytocannabinoids or terpenoids present in C sativa oils, again demonstrating the lack of solid scientific research conducted on them.

In June 2018, the FDA approved Epidiolex, a purified CBD oral solution that was found to provide major reductions in total seizure frequency vs placebo for patients with Dravet and Lennox-Gastaut syndromes. The research on these conditions is the most thorough clinical research that has been performed on CBD and for now should be relied on for understanding CBD’s safety and adverse effects, which will be discussed subsequently in this article. Although the use of CBD has been theorized for a variety of other conditions from migraines and inflammatory conditions to depression and anxiety, only preclinical and pilot studies have been performed for any of these uses, and therefore there is little guidance for physicians if their patient is interested in trying CBD or hemp oils for these conditions.

As for CBD and hemp oils’ potential for use in the treatment of chronic pain, in the most recent review on the topic in 2018, Donvito et al wrote that “an overwhelming body of convincing preclinical evidence indicates that cannabinoids produce antinociceptive effects in inflammatory and neuropathic rodent pain models.” Additionally, it has been reported that CBD may be able to treat addiction through reduced activation of the amygdala during negative emotional processing and has been found to reduce heroin-seeking behavior, likely through its modulation of dopamine and serotonin. Cannabidiol therefore represents an attractive option in chronic pain treatment, particularly in the context of opioid abuse, not only because of its potential efficacy but also because of its limited misuse and diversion potential as well as safety profile. More research will be needed because these were pilot human studies with small sample sizes, but they represent potential future areas of cannabinoid use in the clinical treatment of pain relief and opioid abuse. Additionally, more reflection on the right political and industrial means to go about expanding access to CBD is needed in the context of controversial evidence supporting expanding access to medical marijuana as a pain control option.

In addition, it is important to be aware of the presence of synthetic cannabinoids available on the market, such as “spice.” These substances have severe adverse effects and have led to hospitalizations following ingestion. As to the labeling of concentrations in products, a 2017 survey reported that of 84 online CBD and hemp oil products examined, only 26 were accurately labeled for CBD and THC content, with CBD often being overlabeled and THC underlabeled, consistent with the statements made by the FDA. There have also been documented cases of pediatric THC intoxication related to CBD product ingestion, likely due to this noted variation in products, signaling the need for more regulation of the market.

Cannabidiol and hemp oils are nonintoxicating and potentially useful phytocannabinoid substances that continue to grow in popularity. With increasing patient interest in and use of CBD and hemp oils, more research is indicated to better understand their potential efficacy and purported safety profile. Careful selection of a product is crucial for both safety and potential efficacy, and although the products do not have FDA approval for therapeutic use, patients continue to use them and physicians should inform themselves on both potential safety issues and potential therapeutic benefit. Chronic pain management continues to challenge patients and physicians alike, and investigation into potential therapies such as CBD and hemp oils is a promising area for the future of clinical pain management for both pain relief as well as addiction management. We encourage physicians to not disregard patients’ interest in these therapies and instead to retain clinical curiosity as well as healthy skepticism when it comes to attempts to explore new options, especially in the context of curbing addiction and opioid overuse. Our hope is that this article will inspire physicians to continue to educate both patients and themselves about alternative therapies utilized by growing numbers of the public, with the example of CBD and hemp oils in particular as it continues to come to the forefront of public interest.