In the past few years, dedicated scientists have spent countless hours sticking tiny adhesive discs containing cannabidiol (CBD) and THC onto the skin of small rodents and then studying the results. Through this painstaking research, they've learned a lot about the effectiveness of transdermal patches as a delivery system for cannabis. One important study conducted at the University of Kentucky on rats, for example, suggested that CBD patches can reduce inflammation and relieve the pain of arthritis.
However, it is far more difficult to conduct any kind of research on humans because of archaic federal laws — marijuana is still considered an illegal drug by the feds — and nearly insurmountable bureaucracy, as the National Academies of Sciences, Engineering, and Medicine have chronicled. When it comes to anecdotal evidence of the efficacy of CBD patches, Jeremy Riggle, the chief operating scientist at Mary's Brands, which includes Mary's Nutritionals, Mary's Medicinals and Mary's Whole Pet, points to his former mother-in-law. He said that several years ago she'd broken her ankle, and after trying everything to relieve the debilitating pain, she scheduled ankle-replacement surgery as a last resort. Before the surgery, however, Riggle persuaded her to try a Mary's Nutritionals Elite Transdermal Patch. The outcome: Her surgery was canceled. “She couldn't have been more anti-cannabis before, but it's changed her life,” Riggle said. “Now she's hiking and rafting and she can't stop talking about the patches. We've probably sold 1,000, thanks to her.”
Advantages of Transdermal Cannabis Patches
Patches have long been used by the pharmaceutical industry to deliver compounds, including nicotine, estrogen, testosterone, the high-blood pressure medication clonidine, and the heart drug nitroglycerine. The mechanism is always the same: the patch is applied to the skin and the drug seeps into the bloodstream.
The direct-to-bloodstream path offers several advantages over other forms of cannabis consumption. For starters, delivery of the active ingredients is slow and steady. “With inhaling,” Riggle said, “you get a high dose right away, which your body metabolizes quickly. There's instant stimulation of the endocannabinoid system [ECS]. With slower, prolonged delivery, you can get the endocannabinoid system to where it's functioning optimally.”
Secondly, patches don't have the toxic byproducts of consumption methods such as smoking or vaping.
Transdermal patches also offer a key benefit over oral methods of consumption — tinctures, edibles, or sublingual sprays, strips, or drops. Consuming cannabis orally is what's known in pharmacology as “first-pass metabolism.” That means the active ingredient passes through your digestive system and then your liver before it reaches its intended destination; in the case of cannabis products, that's the ECS. As a result of that first pass, potency is greatly reduced. “If you orally consume 10 milligrams of THC or CBD, roughly half of that will be metabolized during a first pass,” Riggle said. Transdermal patches sidestep that dilution.
One final advantage: better control. “You can find out what dose works best for you,” Riggle said, “and then get the same precise dose every time.”
Dosing With Transdermal Patches
Riggle offered some suggestions for determining the best dose. First, use multiple patches, or try cutting a patch in half. Place the patch directly against the skin, preferably on an area with a lot of veins, such as the inside of the wrist.
Further, not all transdermal formulas are made the same way. For transdermal patches to work, the cannabinoids need to penetrate the stratum corneum, the outer layer of the skin that defends the body from pathogens. That means pairing those cannabinoid molecules with the pharmaceutical equivalent of a battering ram that will help the molecules crash through the skin barrier. Fats such as oleic acid and lecithin can fill this role, and they are among the ingredients in some transdermal patches.
Advantages of Cannabis Patches
Transdermal patches are discreet, relatively inexpensive, and fast-acting. For example, Mary's Nutritionals Elite Transdermal Patch contains 10 milligrams of CBD and offers an onset time of about 15 to 30 minutes. The 40-milligram Pure Ratios Transdermal Reservoir Patch with CBD hemp oil has an estimated duration of up to 96 hours. Those qualities have a lot of people excited about the transdermal delivery of cannabis, including some medical professionals.
“I think CBD transdermal patches are another tool in our toolkit, one that can potentially lead to better pain management while also reducing the reliance on opiates as the pain reliever of choice,” DiMeo said. Convenient and safe, CBD patches might offer a reasonable approach, DiMeo said, for dealing with mild to moderate post-surgical pain during recuperation, or the pain from overuse injuries such as Achilles tendinitis, runner's knee, or tennis elbow.
Patches also are available with cannabinoids other than CBD. Mary's Medicinals offers six different profiles, which include CBD, THC-Sativa, THC-Indica, THCA, cannabinol (CBN), and 1:1 CBD:THC. Papa & Barkley offers a similar range. While CBD alone has proved effective in reducing inflammation, other formulation can be effective for a wide range of ailments, including sleep and anxiety issues. For casual users of cannabis, however, more THC-rich profiles might produce a pronounced buzz, so don't try them before that big job interview.
As with other types of cannabis consumption, novices are advised to “start low and go slow.”
“The current problem with cannabinoids right now is that you can't generalize when it comes to dosing,” Riggle said. “Each person is different in their metabolism, specific indication, level of hydration (which influences drug efficacy), tolerance, BMI [body mass index], etc. So you can't have a one-dose-fits-all approach. A 10-milligram CBD patch may be too low of a dose for some, but certainly not all.”
And one more bit of advice from the experts: While transdermal patches can offer full-body pain relief and relaxation with the flick of a wrist, take the time to find the ratio and dose that works best for you.
Featured image: Athletes use transdermal patches that contain varying ratios of CBD and THC to maximize performance and alleviate aches and pains. (Photo courtesy of Papa & Barkley)