Human and pet products containing the two most common cannabinoids, tetrahydrocannabinol (THC) and cannabidiol (CBD), have become more widely available, and not only in jurisdictions that have passed legislation allowing the sale of products intended for human use. Evolving regulatory frameworks and social perceptions have renewed interest in the potential therapeutic properties of cannabinoids for animals.
As a result, the veterinary profession is being asked to weigh in on the potential roles of CBD and other cannabinoids for animals. An online survey of veterinarians based in the US in 2018, showed that over half of the respondents had clients inquire weekly or monthly about the use of CBD in pets, and these cannabinoids have only increased in popularity over the last two years.
In a recently published research article in the journal “Frontiers in Veterinary Science”, Canopy Animal Health compared the relative safety of three cannabis oil formulations in a randomized, placebo-controlled, blinded study that included 20 healthy dogs. Since a hallmark dosing strategy for cannabis for humans and animals is to “start low and go slow”, the dogs were given up to 10 escalating doses over a period of 32 days, with a minimum of three days between consecutive doses. Clinical observations, physical examinations, and blood collections (complete blood count, clinical chemistry, cannabinoids and their metabolites) were used to assess safety and tolerability of the formulations in the dogs.
For the first time, research showed comparative evidence that–at the investigated doses–a CBD-predominant oil formulation was safer and better tolerated in dogs than oil formulations containing higher concentrations of THC. CBD was well-tolerated by dogs, even when administered at doses up to ~60 mg/kg. These findings support continued research on the safety and potential therapeutic uses of orally delivered CBD in canines.
This study also allowed for the identification of adverse events that may occur with high doses of THC. Encouragingly, these adverse events were transient and resolved with supportive care. In a practice situation, knowing the combination of signs associated with cannabinoid exposure may help guide appropriate diagnosis, support, or treatment.
Canopy Animal Health’s study represents the first and only trial undertaken to assess the safety and tolerability of escalating acute doses of CBD and THC, alone or in combination, specifically in canines. Having a clear idea of the dose tolerability in dogs can be very important to the veterinary practitioner.
Veterinary professionals are the primary source of safety information for pet owners. With the popularity of CBD products on the market, their knowledge base on cannabinoid safety is critical when counselling pet owners considering the use of cannabinoids, or in cases of exposure to the growing number of products in the marketplace.
Due to the wide availability and growing interest in CBD and THC products, veterinarians must be informed about the safety of these compounds and be able to comfortably converse about them with pet owners. Hundreds of potential toxicities involving cannabinoid substances are reported to poison control centers annually and the vast majority of these involve exposure to THC-containing products or cannabis intended for recreational use. Veterinarians and veterinary staff should be prepared to recognize signs of toxicity. Research like the study undertaken by Canopy Animal Health and its research partners will continue to expand the knowledge base on cannabinoid safety in companion animal species and inform veterinary professionals of new findings.
Justyna Kulpa, PhD, Regional Research Manager and Bob Menardi, DVM, Director of Veterinary Technical and Educational Services are in Canopy Animal Health’s division.