CBD for chronic pain: The science doesn’t match the marketing

By | September 24, 2020

If you ask health care providers about the most challenging condition to treat, chronic pain is mentioned frequently. By its nature, chronic pain is a complex and multidimensional experience. Pain perception is affected by our unique biology, our mood, our social environment, and past experiences. If you or a loved one is suffering from chronic pain, you already know the heavy burden.

People are looking for novel, nonaddictive ways to treat pain

Given the ongoing challenges of chronic pain management coupled with the consequences of the opioid epidemic, pain management practitioners and their patients are searching for effective and safer alternatives to opioids to alleviate pain. With the legalization of marijuana in many states and resulting cultural acceptance of this drug for recreational and medical use, there has been an increased interest in using cannabis for a myriad of medical problems, including pain.

Cannabis (most commonly obtained from the Cannabis indica and Cannabis sativa plants) has three major components: cannabinoids, terpenoids, and flavonoids. While there are over a hundred different cannabinoids, the two major components are tetrahydrocannabional (THC) and cannabidiol (CBD). Historically more attention has been paid to the psychoactive (euphoric “getting high”) component of the cannabis plant, THC; there have been fewer scientific studies on the medical use of CBD, a non-psychoactive component of the plant.

What’s the thinking behind using cannabis for chronic pain?

CBD is emerging as a promising pharmaceutical agent to treat pain, inflammation, seizures, and anxiety without the psychoactive effects of THC. Our understanding of the role of CBD in pain management continues to evolve, and evidence from animal studies has shown that CBD exerts its pain-relieving effects through its various interactions and modulation of the endocannabinoid, inflammatory, and nociceptive (pain sensing) systems. The endocannabinoid system consists of cannabinoid receptors that interact with our own naturally occurring cannabinoids. This system is involved in regulating many functions in the body, including metabolism and appetite, mood and anxiety, and pain perception.

What’s the research that CBD works in humans?

Given its promising results in animal models, along with its relative safety, non-psychoactive properties, and low potential for abuse, CBD is an attractive candidate to relieve pain. Unfortunately, there is a lack of human studies about the effectiveness of CBD. However, there is an abundance of commercial advertisements about the magical effects of CBD, and it is frequently presented as a cure-it-all potion that will treat everything including diabetes, depression, cancer, chronic pain, and even your dog’s anxiety!

So far, pharmaceutical CBD is only approved by the FDA as adjunct therapy for the treatment of a special and rare form of epilepsy. Currently, CBD alone is not approved for treatment of pain in the United States. But a combination medication (that contains both THC and CBD in a 1:1 ratio) was approved by Health Canada for prescription for certain types of pain, specifically central neuropathic pain in multiple sclerosis, and the treatment of cancer pain unresponsive to optimized opioid therapy. There is currently no high-quality research study that supports the use of CBD alone for the treatment of pain.

Why is CBD presented to the public this way, when it is not without risks?

Given the rapid change in the legality of cannabis coupled with the increased appetite for something new, and driven by unprecedented profit margins, the advertising for cannabinoids in general and CBD in particular has gone wild. The FDA is very clear that it is illegal to market CBD by adding it to a food or labeling it as a dietary supplement. And it warns the public about its potential side effects, as it’s often advertised in a way that may lead people to mistakenly believe using CBD “can’t hurt.” CBD can cause liver injury, and can affect the male reproductive system (as demonstrated in laboratory animal studies).

Most importantly, CBD can interact with other important medications like blood thinners, heart medications, and immunosuppressants (medications given after organ transplantation), potentially changing the levels of these important medications in the blood and leading to catastrophic results, including death. Also, more information needs to be gathered about its safety in special populations such as the elderly, children, those who are immunocompromised, and pregnant and breastfeeding women.

Many of the CBD products on the market are unregulated

In fact, the FDA has issued several warning letters to companies and individuals that market unapproved new drugs that allegedly contain CBD. The FDA has tested the chemical content of cannabinoid compounds in some of the products, and many were found to not contain the levels of CBD the manufacturers had claimed they contain.

Beware of powerful testimonials

Finally, there is anecdotal wisdom, when experiences by patients and health professionals have positive results. While the experience or medication could be beneficial, that doesn’t mean it is going to work for everyone. That’s because each and every person is unique, and what works perfectly for one patient could have no effect on another patient. This is especially true for pain, where many other factors (our mood and stress level, our environment and other medical conditions, and our previous experiences) can affect the perception of pain. Please be careful, and keep in mind that some of these incredible-sounding testimonials are merely marketing materials meant to lure consumers to buy more products, as the CBD market is expected to hit $ 20 billion by 2024.

The bottom line: Don’t make CBD your first or only choice for pain relief

If you or someone close to you is considering trying CBD, I would recommend Dr. Robert Shmerling’s advice about the dos and don’ts in choosing an appropriate product. Until there is high-quality scientific evidence in humans, it is difficult to make a recommendation for the regular use of CBD in chronic pain management.


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