Cannabinoids and Pets: Promise or Problem?

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Hemp-derived cannabinoids like cannabidiol (CBD) are rapidly making their way into the pet health space, capitalizing not only on the popularity of the cannabinoids themselves but also the ongoing trend of supplement companies more broadly creating products for companion animals.

“We’ve seen a rise in supplements in pets in general as people continue to treat their pets as members of their family. This humanization—we’re seeing that in pet food and treats as well,” explains Scott Dicker, senior market insights analyst at SPINS (Chicago). “And also, the addition of other functional ingredients that have specific health focuses that are traditionally found in human supplements is making its way over to pets. CBD is certainly one of those.”

According to 2020 data from brand strategy firm Finn Cady, one in four dog owners and one in four cat owners report having fed their pets hemp-derived CBD products.¹ Two inthree dog owners and three in four cat owners report that they would do so again. SPINS data states that 68% of dollar growth in CBD in the companion-animal market is coming from the subcategory of treats, and 32% of dollar growth is in vitamins and supplements. Also big: 60% of dollar growth in the pet supplement category can be attributed to CBD.

For manufacturers of hemp-derived cannabinoids, the pet health space is a category in which CBD and other cannabinoids are seeing consistent sales growth—unlike in the human space, where cannabinoid product sales have been slowing down since 2020. “I think it’s worth noting as you see a big decline in human CBD sales—and that’s for a variety of reasons—we do continue to see [CBD] as a bright spot in the pet channel,” says Dicker.

That is not to say that everyone should jump on the pet health CBD bandwagon. There’s a lot you need to understand about the pet space first.

Benefits

Hemp-derived CBD and other cannabinoids have many potential benefits that compel consumers to buy and use these products. For one, the endocannabinoid system is believed to be physiologically involved in the regulation of many bodily functions, including appetite, pain, mood, memory, inflammation, insulin sensitivity, as well as fat and energy metabolism.² Therefore, cannabinoids such as CBD, through activation of CB1 and CB2 receptors, may exert benefits in these areas.

For example, preclinical research in mice found that CBD may have anxiolytic effects as well as immune-modulating and anti-inflammatory properties. A recent large-scale, blinded, randomized clinical trial found that supplementation with CBD and other minor cannabinoids, including cannabichromene (CBC) and cannabigerol (CBG), led to statistically significant improvements in pain, anxiety, sleep quality, and overall quality of life.² It’s also worth noting that CBD has been approved as a drug to treat epilepsy, called Epidiolex. There is, therefore, a draw to hemp derivatives that has made its way to the care and wellbeing of pets.

Research on the effects of CBD and other cannabinoids in companion animals such as dogs, cats, and horses is somewhat limited, but there are promising results here as well.

For example, studies have found positive results for relief from osteoarthritis-related pain. One 90-day study published in the Journal of the American Holistic Veterinary Medical Association found that 30 out of 32 dogs with osteoarthritis that completed the study benefited from supplementation with the CBD oil product, ending the study with reduced pain scores, improved mobility, and improved quality of life.³ At the start of the study, 23 dogs were taking gabapentin as part of their pain management protocol. Ten of these dogs were able to discontinue use of gabapentin following the introduction of CBD oil, and 11 were able to have their daily dose of gabapentin reduced. However, among this study’s limitations is the absence of a placebo group.

One randomized, double-blind, placebo-controlled study of 20 dogs with osteoarthritis found that CBD significantly decreased pain and improved mobility in a dose-dependent manner after four weeks of use.⁴ On the other hand, a different prospective, double-blinded, crossover, placebo-controlled study of 23 dogs found that there were no differences in osteoarthritis between groups at any point during six weeks of treatment in that study.⁵ This study also saw some adverse events among the dogs, including elevated liver enzymes in 14 dogs and vomiting in two. Ultimately, larger, more comprehensive studies need to be conducted to determine the effects of CBD on these and other outcomes more definitively.

That said, many animals may stand to benefit from hemp-derived CBD and cannabinoid products as CB1 and CB2 receptors have been identified in multiple animal species, with dogs having a particularly high density of CB1 receptors in their cerebellum.⁶

Regulation

It should be common knowledge at this point that the U.S. Food and Drug Administration (FDA) does not recognize cannabidiol (CBD) as a dietary ingredient because of the drug preclusion clause of the Federal Food, Drug, and Cosmetic Act. This means that because CBD has been previously investigated as a new drug (and subsequently approved as a drug), CBD does not qualify to be marketed as a dietary ingredient in dietary supplements. While stakeholders argue that hemp-derived extracts such as CBD have been marketed as dietary supplements prior to CBD’s investigation as a new drug, FDA’s stance remains unchanged. That said, the agency has been exercising enforcement discretion in the regulation of CBD products on the market, not taking wholesale action against manufacturers of hemp-derived CBD but instead targeting companies that sell adulterated products that make false and illegal claims.

What’s important to understand about the pet health space is that dietary supplements for animals are not regulated by the Dietary Supplement Health and Education Act (DSHEA), like they are for humans, and therefore they are not recognized as a special category by FDA.

“This is the conundrum: for animals, products are either designated as food or drugs. There is no approval process for dietary supplements in animals,” explains Charlotte Lacroix, DVM, JD, founder and CEO of Veterinary Business Advisors Inc. (Whitehouse Station, NJ). Instead, says Lacroix, the agency within FDA that regulates animal products, the Center for Veterinary Medicine, created Compliance Policy Guide (CPG) Sec. 690.100, essentially exercising enforcement discretion on pet products marketed as supplements. As a result, says Lacroix, “The regulatory status of any product is really going to be determined by the Center for Veterinary Medicine on a case-by-case basis.”

More specifically, the CPG states that CVM will “not generally object to the marketing of nutritional supplements for oral administration to companion animals provided they conform to the following restrictions, 1) there is a known need for each nutrient ingredient represented to be in the product…, 2) the label represents the product for use only in supplementation [of], and not as a substitute for, good daily rations, 3) the product provides [a] meaningful but not excessive amount of each of the nutrients [it] is represented to contain, 4) the labeling should bear no disease-prevention [or] therapeutic, including growth promotional, representations, 5) the labeling should not be otherwise false or misleading in any particular, and 6) the product is neither over-potent nor under-potent nor otherwise formulated so as to [pose] a hazard to the health of the target animal.”⁷

“The problem with CBD is that it’s not a nutrient, and when you’re looking at dietary supplements and what dietary supplements are, it’s really hard for CBD to fall into any of the dietary supplement categories [specified in the compliance policy guide],” says Lacroix, adding that CBD is also still subject to drug preclusion in the animal category.

Importantly, Lacroix points out that given CBD’s regulatory status, federally, veterinarians are, for the most part, prohibited from discussing or recommending the product to their clients. While physicians treating humans, too, need to exercise caution when it comes to recommending CBD and other cannabinoids, veterinarians have very little flexibility in this area.

“Veterinarians have to follow federal law. Veterinarians are not allowed to discuss, to endorse, to recommend, to shelve [CBD products],” explains Lacroix. “There are state exceptions, like California, which does allow veterinarians to discuss it, but the fact of the matter is the law, like so many laws, is not in alignment with reality or practicality.”

In a legal update published in 2019, the American Veterinary Medical Association stated: “Under existing federal and state law, veterinarians who administer, dispense, prescribe, or recommend ‘hemp’ or other cannabis-derived products that are not approved for use in animals, or approved for animals or people in accord with FDA extra-label drug-use regulations, face increased potential legal risk if there is an adverse event. Adverse events can include unintended effects (side effects) of a drug, or it could be that the drug doesn’t deliver the intended therapeutic effect. Legal risk can be heightened if there are approved drugs available to treat the condition and those are not selected as part of a treatment plan or in the absence of a related standard of care.”

Essentially, veterinarians who stick their necks out because they believe in the potential of hemp-derived CBD and other cannabinoids and want to help their clients safely administer the products could be vulnerable to disciplinary action from veterinary medical boards if there are complaints from clients. Because hemp-derived CBD and cannabinoids are not federally allowed in supplements or foods for companion animals, there would be little if any legal defense for recommending or administering the product.

“There’s no question that veterinarians are discussing this, but I think they are tiptoeing because there are no clear guidelines as to what that is—discussing versus endorsing,” says Lacroix. “Common sense would say it’s better to engage in a conversation with your client even if it’s to say you do not recommend using it because there are no methods of controlling the products, there’s no approval process, no quality control, you have no idea what’s in there, or how much is in there.”

This communication gap can be potentially detrimental for brands who want to earn the trust of consumers. While many consumers may believe in hemp-derived CBD and cannabinoids, many others may be unwilling to try it without a veterinarian’s go-ahead. It’s also unfortunate because veterinarians can not only help improve the category’s credibility but also keep animals safe. In states where recreational marijuana is legal, for example, unsupervised administration of tetrahydrocannabinol (THC) in companion animals can lead to adverse events, whereas veterinarian guidance could reduce adverse events and instead provide beneficial effects.

“I don’t understand why veterinarians aren’t being given the same privileges that human physicians have to recommend THC to their patients. I think THC would be extremely helpful to pets if it was being recommended and described how to use in a safe way,” says Robert J. Silver, DVM, MS, founder and medical director of Well-Pet Dispensary (Niwat, CO), and chief veterinary officer for the brand Real Mushrooms for Pets (Canada). “THC can be 100% safe in a pet if it’s done properly, and it can provide an additional increment of value to whatever they’re trying to treat. At the same time, THC can be a problem in pets, so it needs to be administered, it needs to be recommended, it needs to be described how to do it by a veterinarian. And in not a single state in the United States is a veterinarian given the same privileges as a human physician to recommend THC-dominant cannabis.”

Safety

Compared to THC, the safety profile of hemp-derived CBD in animals seems to be much better. For example, one small-scale, uncontrolled preliminary study of eight dogs and eight cats given a 2 mg/kg dose of CBD twice daily for 12 weeks saw “no abnormalities in weekly physical examinations, nor any evidence of organ dysfunction as assessed by blood parameters.” The study did find that cats showed far lower oral absorption kinetics or rapid elimination, suggesting that cats may need different dosing than dogs.⁸

While more clinical research may be required to assess the safety of hemp-derived CBD and other cannabinoids in companion animals, the fact is that these products have already been administered to animals on a large scale, and according to the National Animal Supplement Council (NASC; Sun City West, AZ), there have been very few adverse events.

“First and foremost, people are concerned about animal safety. Nobody wants to see products or ingredients out there that are unsafe. Well, through our adverse event reporting system, we have over 800 million individual administrations of products containing cannabis derivatives in dogs, cats, and horses, with I believe 10 serious adverse events,” explains Bill Bookout, president and founder of NASC. “You can’t tell me by any stretch that this ingredient causes an undue safety risk or concern for the animals that we track, which are non-human food-chain animals. You just can’t make that case. In fact, I can make the case that any clinical study, no matter how rigorously defined, cannot identify everything as when you get a product into the mass marketplace.”

Indeed, there are example of approved drugs for animals that eventually had to be pulled off the market, or that had warnings added because of adverse events that were discovered only when the greater population was exposed to the product. While it’s prudent to assess the safety of a product before it enters the marketplace, the presence of hemp-derived CBD and other cannabinoids in the marketplace currently has not yet proven to be a danger to animals or humans. According to NASC, referring back to its adverse event reporting system, out of 1,124 individual products containing hemp or hemp-derived compounds, and 800 million individual administrations in dogs, cats, and horses, there were 1,595 self-resolving non-serious adverse events, and only 10 serious adverse events that required a veterinarian.

Companies who study cannabinoids, such as ValidCare (Denver, CO) and Radicle Science (San Diego, CA), are hard at work on the human side to demonstrate the safety and efficacy of hemp-derived CBD and other cannabinoids, answering FDA’s call for real-world data on these products.

NASC offers real-world data in the form of its adverse events reporting platform, and has even sponsored a safety study conducted by Nutrasource (Guelph, ON, Canada). In the study, which was just completed and has yet to be published, 32 dogs were administered 5 mg/kg body weight of CBD, a 50/50 combination of CBD and cannabidiolic acid (CBDA), a 50/50 combination of CBD and CBG, or a control, every day over the course of 90 days.

Assessing the safety of CBD and other cannabinoids via adverse event monitoring and clinical research are important resources for an eventual regulatory pathway. And while we have no indication of when a clear regulatory pathway will open up, the fact remains that these products are not going anywhere.

“The industry can’t be left in limbo, human or animal,” says Bookout. “Like it or not, [while] the [2018] Farm Bill did not legalize products—it decriminalized the growing of the agricultural commodity—nevertheless, products started to hit the marketplace. With lack of enforcement—it’s not lack of regulation; it’s lack of enforcement—both human and animal industries developed and now it’s a potentially multibillion-dollar industry.”

As a result, actions that are taken against the industry, as it pertains to hemp-derived CBD and cannabinoids, could have profound economic consequences, he says.

“You can’t just let an industry run for four years or more and then all of a sudden decide you’re going to shut it down,” Bookout states. Simultaneously, the industry has to be proactive where regulators are not. “The industry can’t wait two to three years for the agency to come out with an official position, so we at NASC are going to proactively define what we think is a responsible path forward,” Bookout continues. “So we have testing for products and raw materials that contain cannabinoids, we have labeling guidelines, we have claims limitations, and we have postmarket surveillance, the same as we do for everything else.”

Self-Regulation

While the lack of enforcement can attract unscrupulous elements, there is also the opportunity for self-regulation to demonstrate what responsible industry looks like should FDA change its stance—or, more likely, if Congress changes FDA’s stance. Manufacturers still interested in producing hemp-derived CBD and cannabinoid products for companion animals should seriously consider joining NASC, which offers resources to brands and ensures, to the best of its ability, quality and consistency for animal supplements under its purview.

“NASC was formed, because DSHEA doesn’t apply to animals, with that exact intention: to work cooperatively and transparently with the regulators to achieve an optimal outcome for all stakeholders—but most importantly the animals who consume and benefit from the products,” says Bookout. “FDA allowed [animal supplements] to be marketed under enforcement discretion, provided companies act responsibly. The reason I point that out is that we position CBD exactly the same as we do any of the other products on the market that are marketed under enforcement discretion.

“We feel the compound is certainly different than that which was approved in the drug, and I think there is a pretty solid foundation on the human side for that situation as well. The Center for Veterinary Medicine is consistent with the human side in that [CBD is] an ingredient not approved for use in animal foods, certainly, and it has benefits other than nutrition, but we as an organization position the product like any other botanical extract.”

Where NASC draws the line is at synthetics, he says, “because that would obviously be changing from the substantial equivalency to other botanical extracts that might be 2-4 times in strength.”

NASC member companies can qualify to carry the council’s Quality Seal on their product labels, signaling to consumers that the product meets NASC’s high standards of quality and safety. According to NASC, in order to carry the seal, member companies must successfully pass an independent third-party audit every two years, and demonstrate ongoing compliance with the following criteria: 1) Have a quality-control manual with written standard operating procedures (SOPs) for production process control, 2) Adverse event reporting/complaint system in place to monitor and evaluate products in real time, 3) Comply with stringent labeling guidelines for all products, 4) Display on product labels any specific warnings and caution statements for particular ingredients that are recommended by the Food & Drug Administration’s Center for Veterinary Medicine (FDA-CVM) and the NASC Scientific Advisory Committee, and 5) Submit to random product testing by an independent lab.

Establishing standards and maintaining them is important for the future of any product category. At the end of the day, what hurts hemp-derived cannabinoid products, and the dietary supplement products more generally, is a lack of consistency. Reports of product contents not matching product labels make consumers feel unsafe. In one study of 29 hemp-derived cannabinoid products marketed for pets, for example, four products were positive for heavy metals at or above the lower limit of detection; only 10 were within 90%-110% of the label claims for cannabinoid levels; nine were above 110% of label claims; and 10 were under 90% of label claims.⁹ On a more positive note, 22 of the companies whose products were tested were able to supply a Certificate of Analysis to researchers—and, importantly, all the products were below the federal limit of 0.3% THC.

Resources such as NASC, and practicing transparency through Certificates of Analysis, all serve to establish trust with the consumer. And ultimately, there are limitations to what federal regulators can accomplish. There needs to be cooperation on both sides.

“A lot of people think we’re an unregulated industry,” says Bookout. “I would further add that self-regulation does not mean unregulated. In fact, I would argue that when you have the regulatory agencies working cooperatively with the majority of the industry that’s conducting themselves responsibly, that outcome results in a better regulatory framework, a better regulatory landscape, than having something mandated.”

He continues: “I ask people, how can you regulate quality into an industry—this industry or any other? You can’t regulate quality, and you can’t really regulate compliance, so when you have a majority of the industry acting responsibly and working cooperatively and transparently with regulatory agencies, I would argue that’s the best outcome for everybody involved, including the regulators.”

At the end of the day, both pet supplements and hemp-derived cannabinoid products are categories subject to enforcement discretion by federal regulators. Therefore, manufacturing a hemp-derived cannabinoid pet supplement is not without its risks. However, done responsibly, a successful product can pay off and contribute positively to a growing and evolving industry.

References

1. SPINS report. “SPINS Pet Trends 2020: What’s Driving Today’s Pet Parents.” Published August 28, 2020.
2. Cerino P et al. “A review of hemp as food and nutritional supplement.” Cannabis and Cannabinoid Research, vol. 6, no. 1 (February 12, 2021): 19-27
3. Kogan L et al. “The use of cannabidiol-rich hemp oil extract to treat canine osteoarthritis-related pain: A pilot study.” Journal of the American Holistic Veterinary Medical Association, vol. 58 (Spring 2020): 35-45
4. Verrico CD et al. “A randomized, double-blind, placebo-controlled study of daily cannabidiol for the treatment of canine osteoarthritis pain.” Pain, vol. 161, no. 9 (2020): 2191-2202
5. Mejia S et al. “Evaluation of the effect of cannabidiol on naturally occurring osteoarthritis-associated pain: A pilot study in dogs.” Journal of the American Animal Hospital Association, vol. 57, no. 2 (2021): 81-90
6. Briyne ND et al. “Cannabis, cannabidiol oils and tetrahydrocannabinol—what do veterinarians need to know?” Animals, vol. 11 (2021): 892
7. Finno CJ. “Veterinary pet supplements and nutraceuticals.” Nutrition Today, vol. 55, no. 2 (2020): 97-101
8. Deabold KA et al. “Single-dose pharmacokinetics and preliminary safety assessment with use of CBD-rich hemp nutraceutical in healthy dogs and cats.” Animals, vol. 9, no. 10 (2019): 832
9. Wakshlag JJ et al. “Cannabinoid, terpene, and heavy metal analysis of 29 over-the-counter commercial veterinary hemp supplements.” Veterinary Medicine, vol. 11 (2020): 45-55