Reports of Toxicosis in Pets Rising Since Legalizing Cannabis, OVC Study Finds

A new study from the University of Guelph’s Ontario Veterinary College shows an increase in reports of toxicosis in dogs since cannabis was legalized.

Prior to legalization in 2018, Canada had one of the highest rates of cannabis use in the world, notes the study’s lead author, Dr. Jibran Khokhar, a professor in OVC’s Department of Biomedical Sciences. The uptick since legalization is not necessarily the result of humans increasing their use of cannabis, he added, but could reflect more reporting to veterinarians when animals are exposed.

The study, published in PLOS ONE,  has received extensive coverage in several news outlets, including CNN, NBC News, Popular Science, the New York Post, the Wall Street Journal, Gizmodo, HealthDay, US News and World Report, and WebMD. 

Researchers surveyed more than 200 North American veterinarians (191 of them Canadian) who self-reported over a span of three months in 2021.

They found dogs were the animal most often ingesting cannabis, but cases were also reported in cats, iguanas, ferrets, horses and cockatoos, based on clinical signs, history of cannabis exposure and urine tests. Reported effects included urinary incontinence, disorientation, abnormal or uncoordinated movements, lethargy, increased sensitivity of the senses and slowed heart rate.

The study found edibles were the most common cause of cannabis-induced toxicosis, with animals often ingesting cannabis while unattended. 

While most of the animals had a complete recovery, suggesting no long-term effects, Khokhar noted there were some deaths reported.

Edibles contain other ingredients such as chocolate, which is poisonous for dogs given their inability to metabolize it, so the deaths could be attributed to various factors, he added.

There is no current treatment for cannabis-induced toxicosis in in animals; the study noted most animals were monitored and in a few cases hospitalized for 24 hours at most.

“Our goal is, if we can begin to model it in animals, maybe we can intervene with a drug or an agent that either reverses or blocks the effects of the cannabinoids,” Khokhar said.

That kind of research could help not just pets with accidental ingestions but also children, he added.

Read the entire article on the University of Guelph website.