Why the lack of research on cannabis for animals is harming pets

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Cannabis is not just for humans!

Between 2018 and 2019, the American Society for the Prevention of Cruelty to Animals noted a 765% increase in calls to its Poison Control Center for pets exposed to cannabis.

As cannabis becomes more mainstream to all consumers, so does its availability to companion animals.

(Note: The research reviewed for this story is limited to companion animals. The narrative will be significantly different if – or when – cannabis is introduced to food-producing animals at the farm level.)

The 70-year cannabis prohibition has not been relieved for veterinarians, who are legally forbidden from prescribing cannabis to their patients.

Sadly, veterinarians are outside the loop of cannabis regulations, prompting the American Veterinary Medical Association (AVMA) to recommend that veterinarians not discuss marijuana or cannabis-derived product use to animal/pet owners.

As recently as 2020, the U.S. Food and Drug Administration warned veterinarians that there are too many “data gaps and safety concerns” about cannabinoid therapies for animals.

This has encouraged pet owners to create their own “medical-cannabis” protocols, a practice that could lead to deadly consequences.

However, the federal legalization of hemp in 2018 offered opportunities for veterinarians to explore cannabidiol.

Among other diseases and disorders, several clinical studies have found CBD treatments benefit dogs with seizure disorders and osteoarthritis.

A team of Colorado State University veterinarians, led by Dr. Stephanie McGrath, implemented a randomized blind control study where dogs were provided twice daily doses of CBD-infused oil in conjunction with traditional anti-epileptic medications.

Results indicated that 89% of dogs that received CBD had a reduction of seizures compared with 43% reduction in the control group.

An osteoarthritis study by Cornell University veterinarians, led by Dr. Lauri-Jo Gamble, also involved administering CBD-infused oil to dogs. These results showed an increase in activity levels and “significant decrease in pain,” as reported by owners’ brief pain inventory and Hudson activity scores.

Neither study reported significant adverse side effects or outcomes, and they generally supported CBD use while underscoring the need for additional research.

The success of CBD use in dogs must not be taken loosely, however.

A Canadian study out just this spring studied the prevalence of cannabis-induced toxicity in pets.

The research concluded that as legal marijuana availability rises in North America, there is an increase of intentional or accidental cannabis intoxication in companion pets.

They found that while “most cannabis toxicoses do not result in long-term ill effects … some deaths were reported.”

Although edibles were cited as most common delivery mechanism, secondhand smoke is also a risk factor, according to the highly respected VCA Animal Hospital.

While CBD is largely assumed to be generally safe, dogs are especially sensitive to THC, given the greater abundance of CB1 receptors than are present in humans.

Although not specified, the deaths associated with cannabis intoxication might stem from the concentration of THC or confounded by underlying medical issues and/or effects of known harmful edible matrices such as chocolate or raisins.

Dosing THC in companion animals requires specialized direction by an educated veterinarian, who, ironically, is dissuaded by the AVMA to engage in such conversations.

And ingredients must be labeled on pet-driven cannabis products.

International testing standards organizations have not published testing protocols for veterinary-driven cannabis products and in fact, have yet to recognize the overwhelming needs for the cannabis industry serving companion pets.

Without FDA oversight or regulations by the appropriate veterinary associations and governing bodies, product testing has been minimal at best.

Well-intentioned pet owners might induce cannabis toxicoses that could be fatal, which could potentially lead to allegations of and prosecution for animal abuse.

Clinical studies are sorely needed, and the governing veterinary associations must establish a pathway for open discussion between pet owners and veterinarians to safely provide the best care and opportunities for pet health.

Susan Audino, who holds a doctorate in chemistry, is a chemistry consultant and instructor for the American Association for Laboratory Accreditation. She is based in Delaware.