Safety and tolerability of escalating cannabinoid doses in healthy cats
Objectives: The aim of this study was to determine the safety and tolerability of escalating doses of orally delivered cannabis oils predominant in cannabidiol (CBD), tetrahydrocannabinol (THC), or both CBD and THC in healthy cats.
Methods: In this placebo-controlled, blinded study, 20 healthy adult cats were randomized to one of five treatment groups (n = 4 per group): two placebo groups (sunflower oil [SF] or medium-chain triglyceride oil [MCT]), or three plant-derived cannabinoid oil groups (CBD in MCT, THC in MCT or CBD/THC [1.5:1] in SF). Up to 11 escalating doses of each formulation were delivered orally via syringe to fasted subjects, with at least 3 days separating doses. Safety and tolerability were determined from clinical observations, complete blood counts (CBCs) and clinical chemistry. Plasma cannabinoids (CBD, THC) and metabolites (7-COOH-CBD, 11-OH-THC) were assessed.
Results: Titration to maximum doses of 30.5 mg/kg CBD (CBD oil), 41.5 mg/kg THC (THC oil) or 13.0:8.4 mg/kg CBD:THC (CBD/THC oil) was safely achieved in all subjects. All observed adverse events (AEs) were mild, transient and resolved without medical intervention. Gastrointestinal AEs were more common with formulations containing MCT. Constitutional (lethargy, hypothermia), neurologic (ataxia) and ocular (protrusion membrana nictitans) AEs were more common with oils containing THC (CBD/THC and THC oils). There were no clinically significant changes in CBC or clinical chemistry across treatment groups. Higher plasma levels of the cannabinoids and their metabolites following administration of the CBD/THC combination product are suggestive of a pharmacokinetic interaction.
Conclusions and relevance: This is the first feline study to explore the safety and tolerability of CBD and THC, alone and in combination, in a controlled research setting. These findings will inform veterinarians of the safety profile of cannabinoids, particularly when considering the potential therapeutic use of CBD in cats or recognizing clinical signs associated with accidental exposure to THC-containing products.
Keywords: Cannabidiol; cannabinoid administration and dosage; cannabinoid adverse effects; safety; tetrahydrocannabinol.
Conflict of interest statement
Conflict of interest: JK, GE and DV are employed by Canopy Growth Corporation. LP was previously employed by Canopy Growth Corporation. Staff at VivoCore, and not the authors, were responsible for study conduct and data collection.
Benefits of CBD for animal health
The research for hemp and CBD use has been quickly evolving and we now have a growing body of evidence supporting the benefits of CBD in animals. Look below for a listing of current peer-reviewed journal articles looking at CBD safety and dosing for dogs and cats. Additionally, topics covering osteoarthritis, seizures, and even neoplasia (cancer) have been reported on with respect to CBD in canines. A case study in a horse has been published, and safety studies are expected soon with equines. Read on below for more information and remember that our VetCS team is always here to help you if you have any questions.
Cannabis plants produce over 180 known cannabinoids, with cannabidiol (CBD) being one of those. THC (primary psychoactive component in cannabis) is also a cannabinoid. Other documented, but less researched cannabinoids include: cannabigerol (CBG), cannabinol (CBN), and cannabichromene (CBC).
All mammals have an endocannabinoid system (ECS) that is activated by substances in our bodies called endocannabinoids. Phytocannabinoids are substances like CBD that are produced by plants and function at the same receptors in the ECS. Based on the location of the receptors in the body, therapeutic targets using CBD and hemp can be employed to gain a beneficial outcome.
CBD pet supplements may affect dogs and cats differently
The scarcity of research on how CBD affects dogs and cats matches the abundance of marketing.
Cannabidiol (CBD) supplements and additives for pets rank high on the list of most popular, and promoted, dog and cat product trends. However, the scarcity of research on how CBD affects dogs and cats matches the abundance of marketing. A scientist with one hemp CBD oil-infused pet treat and supplement company, ElleVet Sciences, collaborated with other researchers from several universities to examine how CBD intake influenced dogs’ and cats’ blood composition, as well as the animals’ behavior. In the experiment, CBD supplementation seemed safe for healthy, adult dogs, but a few issues arose in cats that may need further observation.
“Research on the use of things like CBD is still in its infancy despite the very promising anecdotes and affirmative marketing seen in media today,” Christian Kjaer, CEO of ElleVet Sciences, said. The scientists used ElleVet’s hemp CBD oil product in the research.
“Because we are a 'science first' company, we have a commitment to supporting as much of the science being done as possible,” he said.
Research on hemp CDB oil pet supplements
In October, the journal Animals published the results of that study on how CBD-rich hemp nutraceuticals in pets’ diets affect their blood chemistry. The researchers gave two mg/kg total CBD concentration orally to eight dogs and eight cats twice daily. After 12 weeks of this regiment, the dogs showed no clinically significant changes. However, the cats did show some behavioral changes, including excessive head shaking and licking. One cat had increased levels of a certain enzyme. The study authors suggested that CBD receive further study when used with cats to parse out how CBD dosage and other variables affect felines. CBD seemed safe for healthy, adult dogs though.
“Dosing of CBD can be different among different species, but also each individual animal depending on what we are trying to support,” said Kjaer.
ElleVet Sciences is attempting to pinpoint a good starting dose, he said, one that is measurable in the animal’s body with clinical trials and safety studies.
Tim Wall covers the dog, cat and other pet food industries as senior reporter for WATT Global Media. His work has appeared in Live Science, Discovery News, Scientific American, Honduras Weekly, the Columbia Missourian, Global Journalist and other outlets. He holds a journalism master’s degree from the University of Missouri – Columbia and a bachelor’s degree in biology.
Wall served in the Peace Corps in Honduras from 2005 to 2007, where he helped the town government of Moroceli to organize a municipal trash collection system, taught environmental science, translated for medical brigades and facilitated sustainable agriculture, along with other projects.