For skeptics, the suggestion „you ought to try some cannabis for that” has more red flags than a prom date with a neck tattoo.
Fuzzy legal status? Check. Spotty evidence base in the medical literature? Check. Unregulated ingredients, a user base steeped in herbalism and weed, and a kitchen sink full of health claims unrelated to any particular bodily system? Check, check, check.
But when it comes to the so-called cannabidiol molecule derived from the plant Cannabis sativa — aka hemp, a cousin of marijuana without the psychoactive properties — the rise of CBD may not be as flaky as it appears.
„We encourage physicians to not disregard patients’ interest in these therapies and instead retain clinical curiosity as well as healthy skepticism” toward CBD, argues a team of physicians in the latest issue of the medical journal Mayo Clinic Proceedings.
It’s a stark departure from the side-eye directed toward the claims for herbal preparations of days past.
This new receptiveness to investigating CBD is part science, part pragmatism.
Of the latter, Dr. Brent Bauer said when a medicinal craze sweeps the land it does clinicians no good to sit on the sidelines. Bauer is the director of the Complementary and Integrative Medicine Program at Mayo Clinic, and co-author of the Proceedings paper.
„This is our first attempt to say it’s big, patients are using it. What do we need to know as clinicians?” Bauer said. „Our patients have access to a bewildering array of products out there, and we don’t do them a service if we say to everything, 'we don’t know, we don’t trust it, therefore we can’t talk about it.'”
If CBD is having a moment, one reason for the craze begins with an unlikely agent for change: the farm bill. The 2018 legislation legalized the sale of hemp containing less than 0.3 % THC, the psychoactive molecule found in marijuana. A wave of vendors selling CBD that can be taken topically, orally and even under the tongue — a dropper-based method called a tincture — have emerged.
Because the CBD molecule is not patented, none of these vendors are regulated by the FDA. That means consumers have little idea whether they are buying CBD-labeled salves, soaps and foods containing large or trace quantities of cannabidiol.
Independent efforts to lab-test CBD goods have discovered the contents of various brands span a broad range of quality. Concerned vendors have taken to displaying lab reports and touting the transparency of their supply chain, but other products bearing the same chemical name can be purchased at gas stations.
And it’s still a health treatment with a thousand preparations. „We don’t have a level playing field,” Bauer said. „When we talk about CBD, are we talking about oils, tinctures, capsules, gummies cookies, pop? All of a sudden we’ve got CBD coming out of our ears. That’s the challenge.”
In another twist, CBD was approved last year as a prescription medication called Epidiolex, an extract of CBD for the treatment of two rare forms of epilepsy. The fact that CBD succeeded where the titans of pharmaceutical R&D have failed raises its own question: What exactly does CBD do in the body?
CBD, as it turns out, finds receptors in the human nervous system more or less built to receive CBD, or our human forms of CBD, anyway. For researchers unaccustomed to imagining linkages between human and plant biochemistry, the presence of these intra-cellular human forms of CBD, chemicals known as endocannabinoids, is striking.
„Certainly I wasn’t trained in that back when I went to medical school many years ago,” Bauer said. „But we have this system using natural cannabinoids that our body makes. A lot of people look at that system as kind of a moderator, one where if certain neurons are over-firing, the endocannabinoids help slow those down, and if some neurons need to speed up, they help them speed up. We are starting to realize we can modulate or impact those receptors with CBD products.”
If the list of claimed uses for CBD is long (it includes pain, anxiety, addiction and sleep) that may reflect the fact that CBD messengers communicate at over 65 different locations throughout the body, correcting imbalances known as inflammation.
„Inflammation is currently linked to cancer, heart disease, arthritis, rheumatologic disorders,” Bauer said. „Inflammation is an early pathway to a lot of diseases, so any time you can hit inflammation broadly, you could have an impact on a lot of different things. So, I think it’s theoretically plausible … for CBD to hit a lot of targets … but at some point are we getting into the placebo effect, and those are questions that can only be answered with well done clinical trials.”
In the meantime, caution is the best approach.
„There is no free lunch, even though CBD is natural,” he said. „Tobacco is natural, too. So is strychnine. Just because it’s natural, don’t go out and rush into something. If you have ever had liver problems, I’d probably stay away from it. If you’re on a lot of drugs, I wouldn’t start CBD without talking to your care team.
“If we can get everybody to tap their brakes and talk to their doctors, do a little homework, give it a little time for the science to catch up, I think we’ll find it’s probably useful for some things, but not useful for everything.”