Is CBD safe and helpful? More human studies needed, says Mayo Clinic study

26 Aug 2019 --- A growing body of pre-clinical and clinical evidence suggests that cannabidiol (CBD) oils may hold promise for treating conditions such as chronic pain and opioid addiction, according to a review of the latest research on the subject, to be published in September in Mayo Clinic Proceedings. However, the authors note that more research involving humans is needed before health care providers can definitively classify CBD as helpful and safe. With their latest findings, the researchers are advising physicians to expand their knowledge on the cannabis extract to best advise their patients.

CBD oils and products have become increasingly popular with consumers as ways to find relief from aches and pains, anxiety, sleep disturbances and other chronic issues. However, most studies of the cannabis extract have been conducted on mice.

“There are many intriguing findings in pre-clinical studies that suggest CBD and hemp oil have anti-inflammatory effects and may be helpful with improving sleep and anxiety,” says Brent Bauer, M.D., Director of Research for the Mayo Clinic Integrative Medicine program. “But trials in humans are still limited, so it is too early to be definitive about efficacy and safety.”

Dr. Bauer asserts that there is reason for concern about a growing number of reports of liver injury in patients who have used CBD products. With increasing patient interest in CBD and hemp oil products, it is important that clinical research moves ahead to better understand their potential value and safety, he highlights.

“Careful selection of a health care product is crucial, and though these products do not have Food and Drug Administration (FDA) approval for therapeutic use, patients continue to ask for them and use them. Physicians need to become better informed about these products, and it's important that human trials examine issues of efficacy and safety,” says Dr. Bauer.

With CBD a hot consumer trend, physicians may find it easy to dismiss it as unproven and untested, note the researchers. Dr. Bauer encourages health care professionals develop expertise on these products and not to easily dismiss their patients’ interest in CBD.

“We encourage physicians to not disregard their patients’ interest in these products and keep both a clinical curiosity and a healthy skepticism about the claims made,” he says. “Chronic pain management continues to challenge patients and physicians, and these therapies are a promising area that needs more research. For patients struggling with chronic pain, physicians taking time to listen to them and address their questions compassionately but with an evidence-based approach can help them make informed decisions.”

The variety of CBD and hemp oil products, and the limited regulation of these products, is a concern for health care professionals, according to the study.  The variability of state laws regarding production and distribution of hemp and CBD products adds to the complexity of decision-making for consumers and physicians.

No rigorous safety studies have been done on “full spectrum” CBD oils, which contain a variety of compounds found in the hemp plant, not just CBD. Moreover, there are important distinctions between marijuana, hemp and the different components of CBD and hemp oil, and some clinicians may not be aware of them, as highlighted by coauthor Karen Mauck, M.D.

“Other than Epidiolex, a purified form of plant-derived CBD which was approved in 2018 for treatment of severe forms of epilepsy, all other forms of CBD are not approved by the FDA but are sold in a variety of formulations, including oral or topical oils, creams, sprays and tablets,” says Dr. Mauck. “They contain variable amounts of CBD, may contain other active compounds and may have labeling inaccuracies. Before using CBD or hemp oils, it's important to consult with your physician about potential side effects and interactions with other medications.”

The legalization of marijuana for medicinal purposes has spurred intense interest by consumers in over-the-counter products containing CBD and hemp oil, which are now available in a broad range of edible, topical and vapable formats.

By Benjamin Ferrer