Smoking Marijuana More Effective Than CBD Extracts for Back Pain

By Pat Anson, PNN Editor

One of the reasons many medical marijuana users prefer edibles over smoking is that they are perceived as healthier.  Marijuana smoke contains many of the same chemicals and carcinogens as cigarette smoke, and could have harmful effects on people with respiratory or cardiovascular problems.

But a small new study conducted in Israel found that smoking marijuana is better than ingesting it, at least when it comes to treating chronic lower back pain. Researchers enrolled 24 adults with MRI or CT scans that showed evidence of disc herniation or spinal stenosis, and had them try two different types of cannabis treatment.

The first was a cannabis extract rich in cannabidiol (CBD), which was taken sublingually under the tongue daily for 10 months. After a month of no treatment, the same group smoked cannabis flowers rich in tetrahydrocannabinol (THC) up to four times a day for 12 months. Participants were allowed to take pain medication as needed, including oxycodone and acetaminophen.

The study findings, published in the Rambam Maimonides Medical Journal, showed there was little to no improvement in back pain when participants took the extract, but significant improvement when they smoked cannabis. The use of analgesic drugs also dropped significantly while smoking.

Notably, three patients dropped out of the extract phase of the study because it wasn’t helping them, but then returned to participate in the smoking phase.

“The current study is the first, to our knowledge, to indicate that THC-rich smoked therapy is more advantageous in ameliorating LBP (lower back pain), than low THC CBD-rich sublingual extracts. Despite the small number of patients, our data indicate that THC-rich smoked therapy is helpful in mitigating LBP,” researchers reported.

The most commonly reported adverse events during the study were nausea, dizziness, drowsiness and fatigue during the extract phase; sore throat and drowsiness were reported during the smoking phase. All of the adverse symptoms disappeared after a dose tolerance was reached. Most of the adverse effects were in female patients.

A 2019 study of medical marijuana users also found that smoking cannabis provided more pain relief than ingesting it. Over 3,300 people logged their symptoms on a mobile app while using a variety of cannabis products, including dried flower, edibles, tinctures and ointments. Smoking the dried flower provided more pain relief than any other cannabis product, regardless of the amount of THC.

Another problem with CBD edibles is that they are frequently mislabeled. A recent study of 80 CBD oils found that only 43 had concentrations of cannabidiols that were within 10% of their label claims – an accuracy rate of just 54 percent.

Heavy Metals and Plastic Residue Found in Many CBD Products

By Pat Anson, PNN Editor

Yet another study has found evidence that cannabidiol (CBD) products are frequently mislabeled, with over half of the edibles and topicals tested containing significantly more or less CBD than their labels indicated. Researchers at the University of Miami School of Medicine also found that many CBD products are contaminated with low-levels of heavy metals and plastic chemicals.

“Because the cannabis plant is recognized as a bioaccumulator, which is highly effective at absorbing and retaining contaminants (e.g., heavy metals) in soil, it is important to characterize the degree of contamination in CBD products and their label accuracy to better estimate potential health benefits and risks associated with consumption,” researchers explained in the journal The Science of the Total Environment. 

Investigators analyzed 516 CBD products that were purchased online or at retail stores and had them tested at Ellipse Analytics in Denver. About a quarter of the CBD products were edibles.

Less than half of all the products tested had CBD concentrations within 10% of their label claims. Forty percent of the products contained significantly less CBD than claimed by the manufacturer, while 18% contained significantly more CBD.

Of the edible products analyzed, 42% tested positive for the presence of lead, 37% tested positive for mercury, 28% tested positive for arsenic, and 8% tested positive for cadmium. Most contained only trace amounts of heavy metals, but four edibles had lead levels that exceeded California’s recommended limit for daily lead consumption.

THE SCIENCE OF THE TOTAL ENVIRONMENT

Many of the edibles also contained low levels of plastic chemicals – known as phthalates – that are designed to make plastics more flexible. Phthalates leach off plastic and have become pervasive in the air, soil and water. Some phthalates have affected the reproductive systems of animals, although their impact on human health is not clear.

The percentage of CBD edibles with detectable phthalate concentrations ranged from 13% to 80% across four phthalates, with DEHP being the most prevalent. DEHP has been linked to cancer, birth defects and other reproductive harm. Federal law prohibits the manufacture and sale of children’s toys and child care products containing DEHP at levels greater than 0.1%. 

“Low-level contamination of edible CBD products with heavy metals and phthalates is pervasive. There is substantial discrepancy between the product label claims for CBD potency and the amount measured in both edible and topical products, underscoring the need for tight regulations for CBD product label integrity to protect consumers,” researchers concluded.

“Given that the consumer demographic purchasing CBD products includes those afflicted with pain, insomnia, anxiety, and other health conditions, these findings could give consumers and medical practitioners hesitation about the benefits and potential harm of CBD use.”

The study was funded by Jazz Pharmaceuticals and the Clean Label Project, a non-profit that seeks to improve food and consumer product labeling.

Previous studies have also found that many CBD products are mislabeled. A recent study at the University of Kentucky College of Medicine found that only half of the CBD oil products had concentrations of cannabidiols that were within 10% of their label claims. Researchers also found that most CBD oils contained trace amounts of THC (tetrahydrocannabinol), the psychoactive substance in cannabis, including some oils that were labeled "THC Free."

With Little Regulation, Many CBD Products Are Mislabeled

By Pat Anson, PNN Editor

CBD (cannabidiol) is being touted as a treatment for nearly everything these days, from pain and anxiety to insomnia and high blood pressure. There’s even talk about CBD as a potential treatment for COVID-19.

But how much do we really know about the CBD edibles, beverages, oils and other products being sold over-the-counter without a prescription? Are the labels accurate? Are they really free of THC (tetrahydrocannabinol), marijuana’s psychoactive ingredient, as some manufacturers claim?

A new study by researchers at the University of Wisconsin School of Pharmacy should give pause to consumers who put their faith in labels and a cannabis industry that is largely unregulated. The researchers bought 39 CBD products from retail stores in southwest Wisconsin and analyzed them in a laboratory.

Their findings, recently published in the journal Epilepsy & Behavior, found that the vast majority of CBD product labels are inaccurate, containing either too much CBD, too little or none at all. And some products that claimed to be “THC Free” contained enough to give you a good buzz, whether you wanted it or not.

“Our data demonstrate that despite warning letters issued by FDA over the past few years a substantial number of readily available CBD formulations continue to be mislabeled,” researchers reported. “In some cases, products labeled as having CBD contained virtually no active ingredient. This was particularly true for the aqueous (beverage) products.”

Of the 21 CBD-infused beverages that were tested, only one was accurately labeled. The vast majority (78%) were “over-labeled” – meaning they contained less than 90% of the CBD they were supposed to have. The rest (14%) were “under-labeled” – meaning they had 110% or more CBD than the label indicated.

Other products tested, such as edibles, oils and transdermal patches, weren’t much better. Only about a third of the oils (36%) were appropriately labeled with the right amount of CBD, and one oil made by HempLucid contained enough THC to cause intoxication if someone consumed less than half a bottle.

“We found that over half of the studied oil-based products contained measurable THC. This may be of concern not only for the potential of adverse, or at least unexpected, CNS effects, but THC contamination may also create difficulty for patients who are subject to testing for illicit drugs by their employers, parole officers, and even by their own providers in some states as a prerequisite for continued prescribing of controlled substances,” researchers warned.

The concern about THC showing up in drug tests isn’t an idle one. A recent study at Massachusetts General Hospital found THC in nearly 80% of the urine samples from patients who reported using CBD products, including some who thought they were only consuming CBD.

A recent study by Leafreport had findings that were similar to the University of Wisconsin study. Out of 221 CBD products tested, 60% didn’t match their label claims. On average, the CBD content was off from the label by nearly 25 percent.

Although the 2018 Farm Bill legalized the use of hemp-based products that contain less than 0.3% of THC, the FDA has yet to adopt new rules to regulate the cannabis industry. The FDA says it cannot issue regulations until more is known about the safety of CBD products, so for now the agency is “monitoring the marketplace” and only rarely taking enforcement action.

The FDA is well aware of the discrepancies in CBD labeling. A 2021 study by the agency of 147 cannabis products found that less than half contained CBD within 20% of their label declarations. But as long as a company doesn’t make therapeutic claims about their CBD products or call them food supplements, the FDA will probably leave them alone, even if their labels are inaccurate.

Study Finds ‘Moderate' Evidence Marijuana Treats Pain

By Pat Anson, Editor

The American Medical Association, the nation’s largest medical group, still officially considers medical marijuana “a dangerous drug and as such is a public health concern."

But studies being published this week in JAMA, the AMA’s official journal, highlight the slim but growing body of evidence that cannabis can be used to treat pain – as well as the lack of standards regulating medical marijuana in states where it is legal.

In a review of nearly 80 clinical trials involving over 6,400 patients, researchers found “moderate-quality evidence” that cannabinoids –  chemically active compounds in marijuana – are effective in treating chronic neuropathic pain and cancer pain, as well as muscle spasms and stiffness caused by multiple sclerosis.

There was “low-quality evidence” suggesting that cannabinoids are effective in treating sleep disorders, weight loss, Tourette syndrome, and symptoms of nausea and vomiting caused by chemotherapy; and “very low-quality evidence” for treating anxiety.

Some of the side-effects associated with medical marijuana were dizziness, dry mouth, nausea, fatigue, somnolence, euphoria, vomiting, disorientation, drowsiness, confusion, loss of balance, and hallucination.

"Further large, robust, randomized clinical trials are needed to confirm the effects of cannabinoids, particularly on weight gain in patients with HIV/AIDS, depression, sleep disorders, anxiety disorders, psychosis, glaucoma, and Tourette syndrome are required. Further studies evaluating cannabis itself are also required because there is very little evidence on the effects and AEs (adverse events) of cannabis," the authors write.

An accompanying editorial in JAMA also called for more research and lamented the lack of evidence supporting the legalization of medical marijuana in 23 U.S. states and the District of Columbia.

"If the states' initiative to legalize medical marijuana is merely a veiled step toward allowing access to recreational marijuana, then the medical community should be left out of the process, and instead marijuana should be decriminalized," wrote Deepak Cyril D'Souza, MD, and Mohini Ranganathan, MD, of the Yale University School of Medicine.

"Conversely, if the goal is to make marijuana available for medical purposes, then it is unclear why the approval process should be different from that used for other medications… Since medical marijuana is not a life-saving intervention, it may be prudent to wait before widely adopting its use until high-quality evidence is available to guide the development of a rational approval process."

The Trouble with Edibles

A second study published in JAMA looked at marijuana edibles – cookies, brownies, candies and other foods containing cannabis – that are being sold at dispensaries in Los Angeles, San Francisco and Seattle.

An estimated 16% to 26% of cannabis patients consume edibles. Many are essentially homemade products that vary from dispensary to dispensary.

Researchers found that many of the edibles had lower amounts of THC (tetrahydrocannabinol) – the active ingredient in marijuana that makes people “high” – than their labels indicated. Over half had significantly higher amounts of THC, putting patients at risk of unintended side-effects.

Of the 75 edible products that were analyzed in a laboratory, only 17% were accurately labeled with THC, 23% were “overlabeled” and 60% were “underlabeled.” The greatest likelihood of obtaining an underlabeled edible was in Seattle.

A little over half (59%) of the edibles tested had detectable levels of cannabinoids.

"Edible cannabis products from 3 major metropolitan areas, though unregulated, failed to meet basic label accuracy standards for pharmaceuticals," the authors write. "Because medical cannabis is recommended for specific health conditions, regulation and quality assurance are needed."

The lack of regulation was highlighted last year in Colorado – where both medical and recreational use of marijuana is legal. A brand of brownie mix, Rice Krispy treats and candy made with cannabis was recalled after inspectors found the edibles contained marijuana that had been “cleaned” in a washing machine.