Alea Sabry & Claire Viscione, National Center for Health Research
Cannabis, a substance in marijuana, is becoming increasingly mainstream across the U.S., and a related substance is on the rise: cannabidiol (CBD). Products like lotions, gummies, soap, and dietary supplements containing CBD are found almost everywhere in the U.S., from gas stations to retailers to news-stands.1 Many companies include CBD as a main ingredient in food, beverages, and cosmetic products, with it mainly sold in oil, extract, capsule, and vapor forms.2,3 Companies selling CBD products claim that these products increase relaxation, decrease anxiety, and have anti-inflammatory qualities, but what does the research say? This article will explain what CBD is and look at the research on the safety and effectiveness of its use for medical purposes.
What is CBD?
Cannabidiol (CBD) is one of the more than 540 chemicals in Cannabis sativa plants. Hemp and cannabis are two different varieties of the Cannabis sativa plant, and CBD can be derived from either. These varieties are classified based on the concentration of the psychoactive ingredient in marijuana, tetrahydrocannabinol (THC), which is associated with a “high,” euphoric feeling.4
Plants with less than 0.3% of THC are often referred to as hemp. Plants with more than 0.3% of THC are known as cannabis, or marijuana.5 Although hemp and cannabis plants contain both CBD and THC, the main difference between the two is the amount of each substance they contain.6 Because hemp-derived CBD products contain less THC than cannabis-derived CBD, they are considered legal under federal law and can be purchased in many locations throughout the U.S.4
Although the research is still limited, CBD has been found to not be addictive and is not known to cause dependence or result in abuse, and humans have shown to tolerate it well in clinical studies.5, 7 To date, the only CBD product that is approved by the FDA for medical purposes is Epidiolex, an anti-seizure medication for children who suffer from severe, rare forms of epilepsy.8 Nevertheless, people use CBD to treat a variety of medical conditions, including chronic pain and various anxiety-disorders.5 Later on in this article, we will discuss the research examining these claimed health benefits.
Are CBD Products Legal?
Due to the intoxicating effects of THC, the overall THC concentration in CBD products is important for determining whether or not the product is legal.6 CBD coming from hemp plants contains less than 0.3% THC, and hemp-derived CBD is considered legal on a federal level. On the other hand, CBD extracted from cannabis plants contains more than 0.3% THC, and therefore cannabis-derived CBD is considered illegal under federal law. The Drug Enforcement Administration (DEA) considers products with more than 0.3% THC to be Schedule 1 controlled substances, meaning they have no accepted medical use and a high potential for abuse.5
The 2018 Farm Bill legalized hemp-derived CBD, meaning that it is no longer regulated as a controlled substance on a federal level.9 Because of this, manufacturers do not have to prove that their products are safe or effective before they sell them, as long as they do not make claims about the possible benefits.9 The CBD market is loosely regulated, and the FDA has not created clear guidelines for the production and sale of CBD products.10 Since the government has not enforced restrictions on the marketing of CBD, this helps explain why there has recently been a surge in products with hemp-based CBD.
Given the lack of regulations on the federal level, states make the final determination on whether or not CBD is legal under state law.10 To check and see if CBD is legal in your state, click here for a breakdown by state.11
Is CBD Effective?
The FDA continues to recommend further research on the medical applications of CBD, as it remains a drug of high interest for its possible therapeutic benefits.8 CBD must continue to be tested in clinical trial settings in order to study the safety and effectiveness of its use for various diseases or conditions.9
Currently, the FDA has approved only one CBD product, Epidiolex, for medical purposes. Epidiolex is a prescription drug used to treat childhood seizure disorders, including Lennox-Gastaut syndrome (LGS), Dravet syndrome (DS), and tuberous sclerosis complex (TSC).12 The FDA approved Epidiolex in 2018 based on four double-blind placebo-controlled trials showing that it could significantly reduce the number of seizures that participants were having.13 If you have been using any CBD product besides Epidiolex to treat epilepsy, stop taking it and consult a doctor to find out if the product is safe and consistent with your symptoms.14
Chronic Pain Management
Research is currently being conducted on people living with chronic pain conditions in order to understand whether CBD can help relieve chronic pain. A 2021 survey asked 253 patients from various pain management clinics to self-report the ways they were treating their pain. Sixty-two percent of the pain clinic patients reported that they use CBD for pain relief, stating that it helped with back pain, nerve pain, neck pain, fibromyalgia, and migraines. Of these participants using CBD for pain relief, sixty-seven percent reported that they were able to reduce their intake of pain medications, specifically their use of opioid medication. Overall, participants using CBD reported that it helped reduce their pain symptoms, and most individuals stated that they did not find CBD harmful or addictive.15
In addition, an observational study from 2019 studied patients taking opioids for chronic pain management. All of the participants were between 30-65 years old, experienced moderate to severe chronic pain for at least 3 years, and had used opioids for at least 2 years before completing the study. Ninety-four patients agreed to take hemp-derived CBD gummies for eight weeks. Over half of the participants reported that using CBD allowed them to decrease their opioid use, improve their pain management, and enhanced their sleep quality.16 However, given the lack of controlled clinical trials on CBD for chronic pain management, further research is still needed to see whether or not CBD usage can help reduce opioid intake.16
CBD has also been studied as a potential treatment for people with anxiety disorders. Although there are ongoing clinical trials, CBD is not currently an FDA-approved treatment for anxiety disorders.
A 2020 review was conducted to understand the safety and effectiveness of CBD as an alternative therapy for a variety of anxiety-related disorders. This study reviewed previously published studies, including randomized controlled trials and case studies, and looked at a general range of CBD use in 285 patients with anxiety disorders. These studies included CBD therapy in healthy volunteers as well as patients with generalized anxiety disorder (GAD), social anxiety disorder (SAD), PTSD-related anxiety, and insomnia disorder. The review concluded that CBD use consistently led to a reduction in anxiety symptoms, indicating that CBD may provide an alternative therapy for patients taking various anti-anxiety medications.17 Despite these findings, additional studies are needed to determine the safety and long-term effects of CBD products used to treat these conditions.
What Are the Risks?
Although research suggests there may be potential uses of CBD for various medical conditions, it is important to be aware of the risks associated with its use. Reported side effects may include drowsiness, fatigue, dry mouth, diarrhea, and reduced appetite.2 Some research in animals has shown that CBD could also harm your liver and central nervous system.13 Not enough is known about CBD to fully understand how it can interact with medications. Experts warn not to consume CBD products if you are on medications such as blood thinners.2
Another concern is unreliable labeling of CBD products. A 2020 FDA report looking at the accuracy of labeling on CBD products found that products containing CBD have not been consistently regulated. Of the products included in this report, the study revealed that CBD content was often mislabeled. For example, the FDA tested 41 CBD-infused cosmetic products. Only 14 of these products had the specific CBD content labeled, and 8 of the products contained less than 80% of the CBD amount indicated, while 2 products contained over 120% the amount of the CBD labeled.18 Additionally, some CBD products also contained THC but did not specify this on their labels.19
The FDA can go after CBD products if they misrepresent the ingredients or if the company makes unproven claims about its benefits. For example, if a company claims that their CBD product can diagnose, cure, treat, or prevent disease, the FDA considers the product an unapproved drug and they respond with a warning. In 2019, the Food and Drug Administration (FDA) sent four warning letters to the biggest CBD manufacturers, all of whom had incorrectly labeled the amount of CBD in their products and/or had falsely claimed that their products could cure diseases such as cancer and Alzheimer’s.20
Nevertheless, CBD products are widely sold and there is little information about their safety or effectiveness. In October 2021, the FDA announced a “data acceleration plan,” outlining their strategies for speeding up the research on cannabis-derived products (such as CBD) and studying their safety.21
The Bottom Line
It is possible that CBD could benefit people with several different symptoms, but there is currently no concrete, scientific evidence other than for pediatric epilepsy. Before deciding whether to take CBD supplements, talk to your doctor to determine how CBD may affect you, and be aware that the advertising claims for many CBD products are unproven. The FDA is encouraging more clinical research to understand the science behind CBD and how it could be used in the future, but it currently remains a complicated issue.
All articles are reviewed and approved by Dr. Diana Zuckerman and other senior staff.
The National Center for Health Research is a nonprofit, nonpartisan research, education and advocacy organization that analyzes and explains the latest medical research and speaks out on policies and programs. We do not accept funding from pharmaceutical companies or medical device manufacturers. Find out how you can support us here.
- Corroon J, Phillips JA. A Cross-Sectional Study of Cannabidiol Users. Cannabis Cannabinoid Res. 2018;3(1):152-161. Published July 1, 2018. doi:10.1089/can.2018.0006
- Bauer BA. Mayo Clinic. What are the benefits of CBD — and is it safe to use?. MayoClinic.com. https://www.mayoclinic.org/healthy-lifestyle/consumer-health/expert-answers/is-cbd-safe-and-effective/faq-20446700. Published December 18, 2020.
- Pavlovic R, Nenna G, Calvi L, Panseri S, Borgonovo G, Giupponi L, … Giorgi A. Quality traits of “cannabidiol oils”: Cannabinoids content, terpene fingerprint and oxidation stability of European commercially available preparations. Molecules. 2018; 23(5): 1230. https://www.mdpi.com/1420-3049/23/5/1230
- Grinspoon P. Cannabidiol (CBD) — what we know and what we don’t. Health.Harvard.edu. https://www.health.harvard.edu/blog/cannabidiol-cbd-what-we-know-and-what-we-dont-2018082414476. Published August 24, 2018. Updated August 27, 2019.
- Rubin R. Cannabidiol products are everywhere, but should people be using them? JAMA. 2019; 322(22): 2156-2158.
- Dresden D, Theisen E. What is the difference between hemp CBD and cannabis CBD?. MedicalNewsToday.com. https://www.medicalnewstoday.com/articles/hemp-cbd-vs-cannabis-cbd. Published July 23, 2020.
- World Health Organization. Cannabidiol (CBD) – Pre-Review Report. Geneva. World Health Organization; 2017. https://www.who.int/medicines/access/controlled-substances/5.2_CBD.pdf
- US Food and Drug Administration. FDA Regulation of Cannabis and Cannabis-Derived Products, Including Cannabidiol (CBD). FDA.gov. https://www.fda.gov/news-events/public-health-focus/fda-regulation-cannabis-and-cannabis-derived-products-including-cannabidiol-cbd#farmbill. Updated January 22, 2021.
- Federation of American Scientists. FDA Regulation of Cannabidiol (CBD) Products. FAS.org. https://fas.org/sgp/crs/misc/IF11250.pdf. Published June 12, 2019.
- Esher E. How legal is CBD, really? Your Comprehensive Guide to CBD Law in the United States. GreenState.com. https://www.greenstate.com/business/how-legal-is-cbd-really-your-comprehensive-guide-to-cbd-law-in-the-united-states/. Published April 27, 2021.
- GreenState Staff. Where is cannabis legal in the United States? (Medical marijuana and CBD included). GreenState.com. https://www.greenstate.com/explained/where-is-cannabis-legal-in-the-united-states-medical-marijuana-and-cbd-included/. Published July 20, 2020.
- US Food and Drug Administration. What You Need to Know (And What We’re Working to Find Out) About Products Containing Cannabis or Cannabis-derived Compounds, Including CBD. FDA.gov. https://www.fda.gov/consumers/consumer-updates/what-you-need-know-and-what-were-working-find-out-about-products-containing-cannabis-or-cannabis. Updated March 5, 2020.
- Samanta D. Cannabidiol: A review of clinical efficacy and safety in epilepsy. Pediatric Neurology. 2019; 96: 24-29.
- US Food and Drug Administration. Drug trials snapshots: Epidiolex. FDA.gov. https://www.fda.gov/drugs/drug-approvals-and-databases/drug-trials-snapshots-epidiolex. Updated July 17, 2018.
- Schilling JM, Hughes CG, Wallace MS, Sexton M, Backonja M, Moeller-Bertram T. Cannabidiol as a Treatment for Chronic Pain: A Survey of Patients’ Perspectives and Attitudes. J Pain Res. 2021;14:1241-1250. Published 2021 May 5. doi:10.2147/JPR.S278718
- Capano A, Weaver R, Burkman E. Evaluation of the effects of CBD hemp extract on opioid use and quality of life indicators in chronic pain patients: a prospective cohort study. Postgrad Med. 2020;132(1):56-61. doi:10.1080/00325481.2019.1685298
- Wright M, Di Ciano P, Brands B. Use of Cannabidiol for the Treatment of Anxiety: A Short Synthesis of Pre-Clinical and Clinical Evidence. Cannabis Cannabinoid Res. 2020;5(3):191-196. Published 2020 Sep 2. doi:10.1089/can.2019.0052
- Skelley JW, Deas CM, Curren Z, Ennis J. Use of cannabidiol in anxiety and anxiety-related disorders. J Am Pharm Assoc (2003). 2020;60(1):253-261. doi:10.1016/j.japh.2019.11.008
- Cohut M, Kirsop A. FDA report evaluates CBD product labeling accuracy. MedicalNewsToday.com. https://www.medicalnewstoday.com/articles/fda-report-evaluates-cbd-product-labeling-accuracy#CBD-content-mislabeled,-THC-not-specified. Published October 29, 2020.
- US Food and Drug Administration. FDA warns company marketing unapproved cannabidiol products with unsubstantiated claims to treat cancer, Alzheimer’s disease, opioid withdrawal, pain and pet anxiety. FDA.gov. https://www.fda.gov/news-events/press-announcements/fda-warns-company-marketing-unapproved-cannabidiol-products-unsubstantiated-claims-treat-cancer. Published July 23, 2019.
- Oestreich E. FDA Focuses on Safety With the New Cannabis-Derived Product Data Acceleration Plan (DAP). Food and Drug Law Institute. https://www.fdli.org/2021/12/fda-focuses-on-safety-with-the-new-cannabis-derived-product-data-acceleration-plan-dap/. Winter 2021.