NOT MUCH news has emerged about CBD from the research community to better document its effects since a recent MyLittleBird Well-Being post in Spring, 2019. But with 64 million Americans trying the purportedly non-psychoactive cannabinoid in a recent 24-month period — of whom 22% said it helped them—clarifications may be in order.
Above all, any CBD product purchased outside a medical marijuana pharmacy should contain less than .3% THC — the cannabis ingredient responsible for the “high” and other psychotropic effects. But because they are “supplements,” CBD products are unregulated and unreliable.
In a Penn Medicine survey that found 70% of products mislabeled, some contained no CBD at all while others contained THC above the legal limit. In another survey of CBD products purchased in the Miami area, one-third contained no CBD.
Among CBD products, the topicals—creams, lotions and ointments—rarely have side effects, while oral/ingestible formulations cause adverse health issues in about one-third of users. The most popular CBD products are ingestible “sublingual” tinctures—drops placed under the tongue—which enter the bloodstream, can stimulate the immune system and can produce brain-based results, such as reducing anxiety and insomnia.
On the other hand, even topical CBD can cause systemic effects. Producing topical formulations that penetrate the skin deeply enough to produce some benefit yet not so deep as to reach the bloodstream is tricky, University of Michigan chronic pain researcher Kevin Boehnke told SELF magazine. Whatever depth is reached by a product, questions remain about how much CBD gets there and how much is needed for an effect.
Sleepiness, sedation and lethargy are common side effects of oral CBD products, according to Miami internist Michael Hall. Other serious side effects include elevated liver enzymes, diarrhea, insomnia and possible interaction with prescription medicines. Among side effects considered “non-serious” are dry mouth, nausea, irritability, euphoria, hunger, irritated eyes and fatigue.
Current FDA warnings focus on unsubstantiated health benefits of ingestible CBD: “It is currently illegal to market CBD by adding it to a food or labeling it as a dietary supplement; the FDA has seen only limited data about CBD safety and these data point to real risks that need to be considered before taking CBD for any reason; and some CBD products are being marketed with unproven medical claims and are of unknown quality.
Endocannabinoid receptors in the body, which interact with cannabinoids (CB) that are produced internally, congregate on the skin and throughout the body in different concentrations for each individual. In addition, the amount of cannabinoids produced naturally by each person varies widely. As a result, huge differences in clinical effects of CBD among individuals make it extremely difficult to do well-controlled studies.
In addition, many of CBD’s effects may occur via receptors other than those for cannabinoids, for example, serotonin receptors and those affected by caffeine or associated with taste. “It’s a very promiscuous compound,” said Boehnke, who also believes that credit for at least some of CBD’s pain-reducing effects may belong to additional ingredients in the formulations, such as arnica.
One of the few studies on humans was actually a Phase 2 clinical trial on a CBD transdermal gel—applied to the skin and designed to penetrate into the bloodstream—on 320 patients with knee osteoarthritis. After 12 weeks, the reports of pain from participants using the CBD products didn’t differ significantly from those who got the placebo—although those receiving the gel reported “some reductions in pain and improvements in physical function,” said Boehnke.
The most common uses of CBD are for pain relief (64%), anxiety (49%) and insomnia (42%). In one study, the 15 men who took 300 mg of CBD before a stressful public speaking event became calmer, compared to those who received either a higher or lower dose —while commercially available CBD doses hover around 10-20 mg.
To counter both pain and inflammation, topical CBD products can work directly on specific areas of the body, says Baylor immunologist Matthew Halpert. In a study of 3,000 people at the University of New Mexico, cannabis products with higher THC levels were associated with greater symptom relief, while CBD products with no THC were not.
In animal models, CBD applied on the skin reduced measurable pain and inflammation caused by osteoarthritis. Other studies showed CBD inhibiting inflammatory and neuropathic pain—two of the most challenging types of chronic pain to treat, but which also come and go unpredictably and are thus hard to study.
CBD topicals have also shown good results with skin disorders, including psoriasis, atopic dermatitis and scars, with 20 patients in one small study reporting improved signs and symptoms. Some dermatologists say the most promising role for cannabinoids is in the treatment of itch.
Among CBD products, those labeled “isolate” contain only CBD and require higher doses to create a beneficial effect —compared to “full-spectrum” products that contain a wide range of different cannabinoids, including THC at levels below .3%. (“Broad-spectrum” products contain all active compounds in cannabis except for THC.)
Topicals that are highly rated for pain relief include Lazarus Naturals CBD Massage oil; Moon Mother Massage oil; and Papa and Barkley Releaf Body Oil. Customers report the best effects from topical CBD products when applied every four to six hours.
Among THC-free transdermal patches—with the advantage of dispensing CBD over long periods—the best rated are Green Garden Gold CBD Patch, which lasts for 48 hours; and CBD Living “Reservoir” Patch, for 96 hours.
While older people may experience more pain from arthritis and other causes of inflammation, the ages most likely to use CBD consistently are 18 to 29, at 20% (with 16% for 30-49; 11% for 50-64; and 8% of those age 65 and older). The states with the highest CBD sales in 2019 were California, Florida and New York.
In the burgeoning market of CBD products, nearly half of consumers prefer oils/tinctures, lotions/balms and gummies, while those interested in CBD-infused food such as chocolate is growing, now at 17%. One product, Vital Leaf’s Body CBD Balm, combines the two: a topical ointment that exudes odors of chocolate.
First-time CBD experimenters should be cautious because it acts so differently on each individual depending on so many variables—different individual responses, different formulations different doses. Maybe most important is the variable of timing—especially with edibles, though even topical products might enter the bloodstream. Because cannabis products can take up to several hours to produce an effect, start with a low dose. Then wait before increasing.
Mary Carpenter regularly reports on topical issues in health and medicine.