Cannabidiol (CBD) is a fan favorite for canine companions. Fido chows down on CBD dog biscuits, infused pup cups, bacon-flavored tinctures, you name it. But what about our low-maintenance, independent, feisty feline friends? Cat lovers rejoice: new research looked at how cats respond to cannabinoids.  The findings are quite purrsuasive.
In a recent survey, almost 98% of respondents felt their cat had a behavioral problem  (100% of the cats felt their owners were the problem). Behavioral issues in cats include anxiety and fear, scratching furniture, and urinating outside the box. The survey also indicated that most owners feel comfortable with cannabinoids for situational treatment.
Scientists have confirmed that CBD has benefits for dogs (e.g., relieving osteoarthritis pain  and reducing seizures ). But there no studies that probe even the safety of cannabinoids for cats—until now.
Kulpa et al  herded two dozen healthy cats. They tested different doses of CBD, tetrahydrocannabinol (THC), and CBD plus THC (1.5:1) in the form of distillate from Canopy Growth Corporation. They acclimated the cats to “study housing conditions” (including group exercise and treats) for 10 days—four of the felines refused to acclimate and dropped out of the study, leaving 20 total.
Researchers randomized the cats into five groups. They administered medium chain triglyceride (MCT) oil and sunflower oil as placebos (these were also the carriers for the cannabinoids). The study started with small doses and worked up to higher ones over roughly 7 weeks:
- CBD dosing ranged from 2.8 mg/kg to 30.5 mg/kg
- THC dosing ranged from 3.8 mg/kg to 41.5 mg/kg
- CBD/THC dosing ranged from 1.2/0.8 mg/kg to 13/8.4 mg/kg
The cats weighed about 3-5 kilograms, meaning some ingested major amounts of cannabinoids by the end of the experiment.
Thankfully, all adverse events were mild; the researchers note that “there were no moderate, severe, or medically significant [adverse events].”
Mild adverse events centered on gastrointestinal (GI) issues followed by respiratory, neurologic, and ocular symptoms. These generally occurred based on the dose: the higher the dose, the more events.
GI issues were mostly related to MCT oil rather than cannabinoids. There were 43 GI events from the MCT placebo and one from the sunflower oil placebo. This was particularly true for vomiting and diarrhea; the CBD/THC sunflower-based oil did not cause these symptoms.
The cannabinoids caused drooling with no difference between CBD and THC. High doses of MCT oil also had this effect. Both cannabinoids also caused lethargy although THC more so. THC caused neurological events like ataxia (akin to poor coordination); combining it with CBD did not help. In fact, the researchers believe that combining the cannabinoids made THC more potent as lower relative doses caused more adverse events. The most vocal cats were those administered CBD:THC.
THC also caused the main ocular event, a protruding third eyelid. The respiratory events were chalked up to the stress of being handled and fed oil.
Beyond this, the researchers performed blood measurements. They concluded that over the course of 7 weeks, “no clinically significant changes were observed in [complete blood count] or clinical chemistry parameters, including liver enzymes (ALP, ALT, AST, bilirubin and GGTP).” Remarkably, the one exception was elevated alanine aminotransferase (ALT) in a cat that took the MCT placebo. This went away after a week.
Cannabinoids are relatively safe for cats even at high doses. THC causes more adverse events/clinical signs than CBD; potential benefits of limited doses are unknown. CBD may be an option for feline veterinary medicine. But don’t give cats MCT oil—we ain’t kitten (I know, I know, clawful). 
1- Kulpa JE, et al. Safety and tolerability of escalating cannabinoid doses in healthy cats [published online ahead of print, 2021 Mar 26]. J Feline Med Surg. 2021;1098612X211004215. doi:10.1177/1098612X211004215. [Impact Factor: 2.015; Times Cited: 1 (Semantic Scholar)]
2- Grigg EK, et al. Cat owners’ perceptions of psychoactive medications, supplements and pheromones for the treatment of feline behavior problems. Journal of Feline Medicine and Surgery. 1098612X1880778.doi:10.1177/1098612×18807783. [Impact Factor: 2.015; Times Cited: 4 (Semantic Scholar)]
3- Verrico CD, Wesson S, Konduri V, et al. A randomized, double-blind, placebo-controlled study of daily cannabidiol for the treatment of canine osteoarthritis pain. 2020; 161:2191–2202. [Impact Factor: 6.961; Times Cited: 13 (Semantic Scholar)]
4- McGrath S, Bartner LR, Rao S, et al. Randomized blinded controlled clinical trial to assess the effect of oral cannabidiol administration in addition to conventional antiepileptic treatment on seizure frequency in dogs with intractable idiopathic epilepsy. J Am Vet Med Assoc. 2019;254:1301–1308. [Impact Factor: n/a; Times Cited: 29 (Semantic Scholar)]