ROCHESTER, Minn. -- Cannabidiol (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. But are these products safe, and are they helpful?

A review of the latest research, to be published in September in Mayo Clinic Proceedings, finds there's a growing body of preclinical and clinical evidence to suggest that CBD oils may hold promise for treating conditions such as chronic pain and opioid addiction. But few clinical studies on the safety and efficacy of CBD have been reported, and more research involving humans is needed before health care providers can say definitely that they're helpful and safe, according to Mayo Clinic researchers.

"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., an internist and 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 says there's reason for concern about a growing number of reports of liver injury in patients who have used CBD products. With greatly increasing patient interest in CBD and hemp oil products, it's important that clinical research moves ahead to better understand their potential value and safety, he says.

"Careful selection of a health care product is crucial, and though these products do not have Food and Drug Administration 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."

The legalization of marijuana for medicinal purposes has spurred intense interest by consumers in over-the-counter products containing CBD and hemp oil, especially for chronic pain relief. The review in Mayo Clinic Proceedings summarizes the latest research, as well as the current legal status of CBD and hemp oils, and concludes that the products are potentially useful for chronic pain and addiction management. The study's lead author is Harrison J. VanDolah, athird-year medical student at Creighton University School of Medicine.

With CBD a hot consumer trend, physicians may find it easy to dismiss them as unproven and untested. Dr. Bauer encourages health care professionals to learn as much as possible and develop an expertise about these products, and take their patients' interest seriously.

"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. 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. 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.

Co-author Karen Mauck, M.D., an internist at Mayo Clinic, says 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.

"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 Food and Drug Administration but are sold in a variety of formulations, including oral or topical oils, creams, sprays and tablets," Dr. Mauck says. "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."

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About Mayo Clinic Proceedings

Mayo Clinic Proceedings is a monthly peer-reviewed medical journal that publishes original articles and reviews on clinical and laboratory medicine, clinical research and basic science research. Mayo Clinic Proceedings is sponsored by the Mayo Foundation for Medical Education and Research as part of its commitment to physician education. Visit the Mayo Clinic Proceedings website to view articles. About Mayo Clinic

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