Do Topical CBD Products Actually Do Anything for Pain?
You don’t need me to tell you that CBD (cannabidiol) is everywhere. You can eat it, you can drink it, you can vape it, you can even bathe in it. And although there’s still plenty to learn about this fascinating little compound, fans of it claim that it has some pretty impressive benefits—particularly when it comes to managing pain.
Personally, I always keep a few jars of it at my desk to help with the shoulder and neck muscle tension inherent in a job consisting mainly of typing and holding a phone next to my face. But it turns out that the research behind these claims is pretty sparse, to say the least. Here’s what you need to know before you give topical CBD a try.
What is CBD?
Cannabidiol, commonly referred to as CBD, is a cannabinoid, a type of compound found in cannabis (marijuana). Unlike the more well-known cannabinoid THC (tetrahydrocannabinol), CBD does not produce a high.
Both THC and CBD act on a system of receptors in your body called cannabinoid receptors. You have cannabinoid receptors throughout your body and, so far, researchers have identified two major types: CB1 (found primarily in the central nervous system, including parts of the brain and spinal cord) and CB2 (found mainly in immune system tissues). Interestingly, both have been found in skin. Researchers have also found that while THC can bind to and activate both types of receptors, CBD seems to modulate and somewhat block the effects of CB1 and CB2 receptors. So, any effect that CBD has on CB receptors may actually be more related to regulating and even counteracting some of the actions of THC and other cannabinoids in the brain.
Why does the body have receptors for compounds in cannabis? Well, it doesn’t exactly. Cannabinoids like THC and CBD are similar enough to compounds that your body naturally makes, called endocannabinoids, that they can interact with this system. Normally, the endocannabinoid system is thought to play a role in a variety of functions in the body, helping to regulate things like parts of the immune system, the release of hormones, metabolism, and memory.
If you’re ingesting something that only has CBD in it and no THC, you won’t have significant effects in the brain. This is why CBD is often referred to as being “non-psychoactive,” although that’s clearly a bit of an oversimplification because it does do something to the central nervous system.
More recent research suggests that many of CBD’s effects may occur outside of CB receptors, Jordan Tishler, M.D., medical cannabis expert at InhaleMD in Boston, tells SELF. In fact, according to a recent review published in Molecules, CBD may have effects on some serotonin receptors (known to play a role in depression and anxiety), adenosine receptors (one of the neurological targets for caffeine), and even TRPV-1 receptors (more commonly associated with taste and the sensation of spiciness).
“It actually is a very promiscuous compound,” Kevin Boehnke, Ph.D., research fellow in the department of anesthesiology and the Chronic Pain and Fatigue Research Center at the University of Michigan, tells SELF. “It will bind to receptors in multiple different pathways,” which makes it difficult to know how it might cause noticeable effects.
“Cannabidiol is a super messy drug,” Ziva Cooper, Ph.D., research director of the UCLA Cannabis Research Initiative in the Jane and Terry Semel Institute for Neuroscience and Human Behavior and the department of psychiatry and biobehavioral sciences, tells SELF. “It has lots and lots of targets and it’s not clear how much of its effects on each target contribute to the potential pain relieving effects.”
All of this points to how hard it is to study the specific effects of CBD on its own—which might be why it’s tempting to claim that it’s the cure for everything without a whole lot of research to actually back up all of those claims.
Here’s what the research says about using CBD for pain.
The most common medical reason for which people report using CBD is to manage chronic pain, followed closely by managing arthritis or joint pain. But does it actually work?
When the National Academies of Sciences, Medicine, and Engineering evaluated decades of cannabis research, they concluded that “in adults with chronic pain, patients who were treated with cannabis or cannabinoids are more likely to experience a clinically significant reduction in pain symptoms.”
But that’s not quite as exciting for CBD as it sounds: “We don’t know cannabidiol’s effects on its own,” says Cooper, who was part of the National Academies committee that put together this report. “[The conclusions about cannabis and cannabinoids] were based on what we know about THC or THC plus cannabidiol.”
In fact, the most compelling research they found for using cannabinoids for pain came from a large review and meta-analysis published in JAMA in 2015. For the study, researchers looked at results from 79 previous studies of cannabinoids and various medical conditions, including chronic pain. However, of those studies, only four involved CBD (without THC)—none of which were looking at pain. So although we might assume that CBD is doing something to help address pain—according to the studies involving the whole cannabis plant—we don’t have great evidence to prove it.
“It might be that cannabidiol by itself is helpful for pain, but at this point we don’t know that,” Cooper says.
The studies we do have about CBD for pain are all animal studies. For example, in a 2017 study published in Pain, researchers gave rats an injection into one of their knee joints to model osteoarthritis. Rats then either received doses of CBD or saline directly into an artery in the knee joint. Results showed that, after receiving CBD, rats showed less inflammation in the joint area and fewer pain-related behaviors (like shaking or withdrawing the affected paw or not being able to bear weight in that paw) compared to those that received saline.
Another study published in 2016 in the European Journal of Pain also looked at arthritis in rats but did so with a topical formulation of CBD. After the rats received an injection into one knee joint to model arthritis, they received a gel that contained either 10 percent CBD (in four different total amounts) or 1 percent CBD (the control) on four consecutive days. The gel was massaged into the rats’ shaved backs for 30 seconds each time.
Then the researchers measured the inflammation in each rat’s knee joint, the level of CBD that made it into their bloodstream, and their pain-related behaviors. They found that the rats that were given the two highest doses of CBD showed significantly lower levels of inflammation and lower pain behavior scores compared to those that got the control. The two lower doses didn’t show much of an effect.
But if you’re reading this, you are probably not a rat, which means these results aren’t directly applicable to your life. Although we know that rats do share much of our physiology—including CB1 and CB2 receptors—these studies don’t really tell us if humans would have the same results with CBD.
“There’s really no substitute for doing proper human studies, which are difficult, expensive, and ethically complicated,” Dr. Tishler says. And we simply don’t have them for CBD and pain.
The only thing that comes close is a Phase 2 clinical trial using a proprietary CBD transdermal gel (meaning it’s meant to go through the skin into the bloodstream) in 320 patients with knee osteoarthritis over 12 weeks, which has not been peer-reviewed to date. Unfortunately, in almost all of the study’s measures of pain, those who received CBD didn’t have statistically different scores from those who got placebo. But “they found some reductions in pain and improvements in physical function,” Boehnke says.
So…is CBD cream just an expensive placebo?
It’s totally possible (and actually pretty likely) that any effect you get from a commercially available topical CBD product is a placebo effect or related to some other aspect of the product. But there are a few things going on here that are more complex than they seem.
First off, we don’t know much about the correct dose of CBD needed for a pain-relieving effect. The doses in the rat studies that were effective were pretty large (for a rat, obviously). And the human participants in the Phase 2 clinical trial we mentioned received 250 mg of synthetic CBD topically per day—as much as many consumer topical CBD products contain in a single jar.
And even though the lotion was applied topically in the rat study, it wasn’t applied locally to the knee. Instead, the researchers were really using the topical application to get it into the rats’ bloodstream, or what’s called systemic administration. But you’d likely need a different dose for it to be effective locally (if you applied it just to your aching shoulder, for instance) in a human. We have no idea what that dose should look like.
Does CBD help with arthritis pain?
If you have chronic arthritis pain, you may be wondering about cannabidiol (CBD) as a treatment. CBD, along with delta-9-tetrahydrocannabinol (THC) and other chemicals, is found in marijuana. But unlike THC, CBD is not “psychoactive” — that is, it does not cause the intoxication or high associated with marijuana use.
There’s a good chance you’ve tried it already: according to a Gallup poll in August of 2019, about 14% of Americans report using CBD products, and the number one reason is pain. The Arthritis Foundation conducted its own poll and found that 29% reported current use of CBD (mostly in liquid or topical form), and nearly 80% of respondents were either using it, had used it in the past, or were considering it. Of those using it, most reported improvement in physical function, sleep, and well-being; of note, a minority reported improvement in pain or stiffness.
Perhaps you’ve been tempted to try it. After all, most types of arthritis are not cured by other treatments, and CBD is considered a less addictive option than opiates. Or maybe it’s the marketing that recommends CBD products for everything from arthritis to anxiety to seizures. The ads are pretty hard to miss. (Now here’s a coincidence: as I was writing this, my email preview pane displayed a message that seemed to jump off the screen: CBD Has Helped Millions!! Try It Free Today!)
What’s the evidence it works? And what do experts recommend? Until recently, there’s been little research and even less guidance for people (or their doctors) interested in CBD products that are now increasingly legal and widely promoted.
But now, there is.
A word about arthritis pain
It’s worth emphasizing that there are more than 100 types of arthritis, and while pain is a cardinal feature of all of them, these conditions do not all act alike. And what works for one may not work for another. Treatment is aimed at reducing pain and stiffness and maintaining function for all types of arthritis. But for certain conditions, such as rheumatoid arthritis, conventional prescription medications are highly recommended, because these drugs help prevent permanent joint damage and worsening disability.
In addition, individuals experience pain and respond to treatment in different ways. As a result, it’s highly unlikely that there is a single CBD-containing product that works for all people with all types of arthritis.
What’s the evidence that CBD is effective for chronic arthritis pain?
While there are laboratory studies suggesting CBD might be a promising approach, and animal studies showing anti-inflammatory and pain-relieving effects, well-designed studies demonstrating compelling evidence that CBD is safe and effective for chronic arthritis pain in humans do not exist. A randomized trial of topical CBD for osteoarthritis of the knee has been published, but in abstract form only (meaning it’s a preliminary report that summarizes the trial and has not been thoroughly vetted yet); the trial lasted only 12 weeks, and results were mixed at best. One of the largest reviews examined the health effects of cannabis and CBD, and concluded that there is “substantial evidence that cannabis is an effective treatment for chronic pain in adults.” But there was no specific conclusion regarding CBD, presumably because definitive studies were not available.
Of course, there is anecdotal evidence and testimonials galore, including reports of dramatic improvement by people who tried CBD in its various forms (including capsule, liquid, topical, and spray) for their pain. But we are still waiting for well-designed, scientifically valid, and rigorous clinical trials (such as this one in progress) that are so badly needed to answer the question of just how helpful CBD may be to people with chronic arthritis pain.
Are there downsides to CBD treatment?
As with any treatment, there can be downsides. CBD is generally considered safe; however, it can still cause lightheadedness, sleepiness, dry mouth, and rarely, liver problems. There may be uncertainty about the potency or purity of CBD products (since they are not regulated as prescription medications are), and CBD can interact with other medications. For pregnant women, concern has been raised about a possible link between inhaled cannabis and lower-birthweight babies; it’s not clear if this applies to CBD. Some pain specialists have concerns that CBD may upset the body’s natural system of pain regulation, leading to tolerance (so that higher doses are needed for the same effect), though the potential for addiction is generally considered to be low.
There is one definite downside: cost. Prices range widely but CBD products aren’t inexpensive, and depending on dose, frequency, and formulation, the cost can be considerable — I found one brand that was $120/month, and health insurance does not usually cover it.
Are there guidelines about the use of CBD for chronic arthritis pain?
Until recently, little guidance has been available for people with arthritis pain who were interested in CBD treatment. Depending on availability and interest, patients and their doctors had to decide on their own whether CBD was a reasonable option in each specific case. To a large degree that’s still true, but some guidelines have been published. Here’s one set of guidelines for people pursuing treatment with CBD that I find quite reasonable (based on recommendations from the Arthritis Foundation and a recent commentary published in the medical journal Arthritis Care & Research):
- If considering a CBD product, choose one that has been independently tested for purity, potency, and safety — for example, look for one that has received a “Good Manufacturing Practices” (GMP) certification.
- CBD should be one part of an overall pain management plan that includes nonmedication options (such as exercise) and psychological support.
- Choose an oral treatment (rather than inhaled products) and start with a low dose taken in the evening.
- Establish initial goals of treatment within a realistic period of time — for example, a reduction in knee pain that allows you to walk around the block within two weeks of starting treatment; later, if improved, the goals can be adjusted.
- Tell your doctor(s) about your planned and current CBD treatment; monitor your pain and adjust medications with your medical providers, rather than with nonmedical practitioners (such as those selling CBD products).
- Don’t make CBD your first choice for pain relief; it is more appropriate to consider it if other treatments have not been effective enough.
- Don’t have nonmedical practitioners (such as those selling CBD products) managing your chronic pain; pain management should be between you and your healthcare team, even if it includes CBD.
- For people with rheumatoid arthritis or related conditions, do not stop prescribed medications that may be protecting your joints from future damage; discuss any changes to your medication regimen with your doctor.
The bottom line
If you’re interested in CBD treatment for chronic arthritis pain or if you’re already taking it, review the pros, cons, and latest news with your healthcare providers, and together you can decide on a reasonable treatment plan. Depending on the type of arthritis you have, it may be quite important to continue your conventional, prescribed medications even if you pursue additional relief with CBD products.
We may not have all the evidence we’d like, but if CBD can safely improve your symptoms, it may be worth considering.
Follow me on Twitter @RobShmerling
As a service to our readers, Harvard Health Publishing provides access to our library of archived content. Please note the date of last review or update on all articles.
No content on this site, regardless of date, should ever be used as a substitute for direct medical advice from your doctor or other qualified clinician.
Commenting has been closed for this post.
You might also be interested in…
Medical Marijuana: Facts about cannabis, THC, and CBD
Exploring medical cannabis means becoming a highly educated consumer. You need to learn as much as you can from a variety of sources. This guide is intended to help you make a more-informed decision. This guide can’t tell you whether medical cannabis will alleviate your health conditions or symptoms. But it will provide basic information to help you consider whether medical cannabis is right for you, ideally working openly with your physician and other health care providers.