Cannabidiol is an unusual word that is about to become a lot more familiar.

Cannabidiol (CBD) is the second-largest active component in mari­juana and an important ingredient in medi­cal marijuana.1

Cannabis refers to all products derived from the Cannabis sativa plant.2 And mari­juana refers to the plant’s parts and products that contain significant amounts of tetrahydrocannabinol (THC).2 Cannabis plants that have little THC are called industrial hemp. The cannabis plant includes approximately 540 chemicals,2 with 140 of those being can­nabinoids.3 THC and cannabidiol (CBD) are the main cannabinoids present.2 While THC is psychoactive, CBD is not.4

The body produces its own cannabi­noids, known as endocannabinoids, which are neurotransmitters that bind to cannabi­noid receptors in the nervous system.4 The endocannabinoid system regulates sleep, appetite, pain, immune system responses,4 learning, memory, and inflammation.3

Highs and Lows

One of the main benefits that CBD is believed to have is pain reduction.4 CBD is also believed to act on serotonin receptors in the brain. Therefore, CBD is being inves­tigated to combat anxiety and depression without the addictive qualities of medica­tions such as benzodiazepines, as well as insomnia and anxiety in children who have post-traumatic stress disorder.4

Other conditions CBD may improve are acne, neurodegeneration associated with Alzheimer disease, heart and circulatory issues (including high blood pressure), psychosis, substance use disorder, and diabetes, among others.4

Animal and test-tube studies have even shown promise for CBD as a weapon against breast cancer cells.4

The mighty combination of CBD and THC is being evaluated to treat pain related to multiple sclerosis and rheumatoid arthri­tis, cancer symptoms, and chemotherapy side effects.4

But while there are high hopes for CBD, its actual proven benefits are few. Numerous studies have been or are being conducted on other, potential benefits of CBD. And yet most have been inconclusive because the studies lack a control group, have been done on too small of a group, are animal studies that are not necessarily applicable to humans, or are unreliable for other reasons.2

In June 2018,5 Epidiolex, an oral medication,2 became the only CBD prod­uct approved by the Food and Drug Administration (FDA).6 This is a prescrip­tion oil6 containing purified CBD2 that is used to treat seizures associated with two types of rare and severe2 childhood epilepsy syndromes—Dravet syndrome and Lennox-Gastaut syndrome—against which anti-seizure medications are usually ineffective.1

Hemp and Haw

As with cannabis, the legality of CBD is forever changing.1 While CBD is legal in all 50 states, CBD is subject to restrictions and is classified along with marijuana by the federal government.1 The regulation of the use of medical hemp and marijuana products varies across states, and production and distribution are unregulated.5 CBD products that are derived from hemp and contain less than 0.3% THC are legal under federal law, but those derived from marijuana are not.4 Laws concerning both of these vary by state.4

CBD products are readily available for anyone to purchase, which brings its own set of issues. Because CBD is sold as a supplement rather than as a medication, the FDA does not regulate its safety and purity.1 Therefore, these products may have misleading labels as far as types and levels of ingredients.1 In fact, in one study, of 84 CBD products bought online, more than 25% had less CBD than advertised, and 18 of them contained THC.6

“I don't know where [patients] get their CBD oil,” says Kathy Hansen, CMA (AAMA), who works in prior authoriza­tions with Dartmouth-Hitchcock Neurology in Manchester, New Hampshire, “which I think is the problem. You don't know the quality and can't verify the concentration.”

To find reputable sources of CBD, Alan Carter, PharmD, an independent consultant in the Kansas City area and an adjunct faculty member of the University of Missouri–Kansas City School of Pharmacy advises, “Look for products from companies that only use hemp grown in the U.S. and provide proof of independent third-party testing by an ISO 17025–compliant labora­tory. Broad-spectrum CBD products should contain no THC, but full-spectrum products may contain up to 0.3% THC according to the certificate of analysis provided by the labora­tory. Also, the [certificate of analysis] must indicate the product passed testing for heavy metals, pesticides, and mold contamination.”

Because CBD is not officially approved for most uses, the dosage can be hit or miss. “Start low and go slow with dose increases,” says Dr. Carter. “The lowest dose that provides relief is the goal.”

It’s Only Natural

“I think we should treat all natural prod­ucts with respect,” says Brent A. Bauer, MD, FACP, research director at Mayo Clinic Integrative Medicine and Health in Rochester, Minnesota.

“Remember, anything that is strong enough to help address a symptom or dis­ease is also strong enough to have negative effects,” he notes. Side effects of CBD include diarrhea, appetite and weight fluctuations, and fatigue.4

Patients need to discuss their use of CBD with their health care providers because CBD can interact with some medications.1 For example, CBD can increase the level of the blood thinner warfarin (Coumadin) in the bloodstream.1

“Especially with higher doses,” Dr. Bauer adds, “there have been a few reports of elevated liver enzymes in some users.”

At her previous job in obstetrics and gynecology, Hansen learned that many of her practice's patients used CBD through the medication list they fill out. She has found that some patients undergoing chemotherapy use CBD to battle nausea. “A lot of them don't have a specific condition. [While] some of them say they use it for anxiety,” shares Hansen.

“The data is not so strong that I recom­mend these things routinely,” says Dr. Bauer. “I also do not recommend CBD—or any dietary supplement—without having the patient first focus on a high-quality lifestyle approach—emphasizing good nutrition, daily aerobic exercise, at least 30 minutes of mind-body practice on a daily basis, struc­tured social support, good sleep hygiene, and regular spiritual practice. At that point,” he says, “if they are still having symptoms that might be addressed by CBD, we explore that on an individual basis.”