Niha Zubair, Arivale Clinical Research Scientist, PhD
With yet another state’s voters approving marijuana legalization earlier this month, it seems everybody is talking about CBD.
While there are claims CBD – or cannabidiol – will cure almost anything, two of the biggest topics of interest are its effects on anxiety and pain.
But, is this just another case of a trendy snake oil?
What is CBD?
CBD is one of over 100 “cannabinoid” constituents of the plant Cannabis sativa, aka marijuana or hemp.
While CBD is often described as “non-psychoactive,” a better description is “non-intoxicating,” which distinguishes it from the other major cannabinoid in marijuana: tetrahydrocannabinol, better known as THC.
Let’s first look at the science behind the claims for CBD in relation to anxiety and pain. This Vox article gets it right: “We know basically nothing about CBD.” While there have been many studies in lab rodents, there’s very little human research on CBD for any of its claimed effects, including on anxiety and pain.
CBD binds to receptors in the body that have been shown in animal models to have regulatory effects on fear and anxiety-related behaviors, so there’s a plausible reason to believe CBD could have an anti-anxiety effect. However, human studies have been short term and very small. For example, acute administration of CBD in certain doses reduced the anxiety associated with a public speaking challenge.1 But, there have been no studies of a more chronic administration of CBD for anxiety in humans and no indications it would be helpful in people with anxiety disorders.
With regard to pain, the few human studies that exist have studied CBD and THC (or other cannabinoids) in combination. Even in animals, there have been few studies of CBD alone for pain, so it’s not possible to draw any conclusion about whether CBD has an impact on pain.
In addition to the lack of evidence, there are two major caveats with regard to the use of CBD for anxiety or pain management: dosage and safety.
The Vox article does a good job of explaining the challenge of dosage: research suggests that considerably higher doses than those typically sold commercially are required for CBD efficacy. Alternatively, in some cases there’s a “U-shaped” curve for dose effectiveness, i.e. doses that are either too high or too low are ineffective. Unfortunately, in the majority of cases where CBD is sold, it’s difficult to know what kind of dose you’re getting.
Even more concerning are questions about what you’re getting. The FDA and other watchdog organizations have found evidence of tainted CBD products that not only contain little to no actual CBD but have harmful constituents instead.2,3
Even pure CBD has been questioned in terms of its safety profile. Side effects from CBD are generally mild, with the most common ones in clinical trials including tiredness, diarrhea, and changes in appetite/weight. However, CBD interacts with certain detoxification enzymes that metabolize medications, so use of CBD by people who are using prescription medications could lead to unwanted effects.4
Because of the lack of clinical studies and federal oversight (since, federally, it’s still an illegal substance), we’re in the land of snake oil when it comes to dealing with CBD products sold commercially.
If it were possible to get pure CBD and know what dose you were taking, there might not be any harm in experimenting to see if it’s helpful for your pain or anxiety. But, given the issues with tainted products and unknown side effects, this is a risky gamble.
If you suffer from chronic pain or anxiety, instead of using CBD, consider talking to your doctor about FDA-approved medications for anxiety or explore techniques like mindfulness-based stress reduction – which benefits both chronic pain and anxiety – as safe and effective alternatives.
- Bergamaschi MM, Queiroz RH, Chagas MH, et al. Cannabidiol reduces the anxiety induced by simulated public speaking in treatment-naive social phobia patients. 2011;36:1219–1226.
- US Food and Drug Administration (FDA). Warning Letters and Test Results for Cannabidiol-Related Products. Page Last Updated 11/02/2017. Accessed on 11/01/18 from https://www.fda.gov/newsevents/publichealthfocus/ucm484109.htm.
- Horth RZ, Crouch B, Horowitz BZ, et al. Notes from the Field: Acute Poisonings from a Synthetic Cannabinoid Sold as Cannabidiol — Utah, 2017–2018. MMWR Morb Mortal Wkly Rep 2018;67:587–588. DOI: http://dx.doi.org/10.15585/mmwr.mm6720a5
- Iffland K, Grotenhermen R. An Update on Safety and Side Effects of Cannabidiol: A Review of Clinical Data and Relevant Animal Studies. Cannabis Cannabinoid Res. 2017; 2(1): 139–154.
[Arivale Hot Topics address health stories currently in the news. The Arivale Clinical Team’s commentary on these news articles is not a review of the scientific evidence, nor an endorsement of a specific study, and is not meant as official medical opinion.]