Emma Alter (31) from Toronto started suspecting there was something wrong with her King Charles spaniel, Maggie, when she rejected the treat offered to her. Alter immediately assumed that Maggie had eaten something she shouldn’t have during their morning walk through the park. However, when Alter noticed that the dog could barely stand up and was starting to sway, with weird head movements, she urgently went to an emergency veterinary clinic, and — believe it or not — the vet said Maggie had symptoms of weed poisoning.

Treating this condition cost Alter $2,500 in medication during a three-day treatment at the clinic. In the end, Maggie was fine but was kept on a tighter leash while at public parks, wearing a mask for a little while. 

According to the National Issues Committee at the Canadian Veterinary Medical Association, this isn’t an isolated case — taking into account the recent legalization of cannabis edibles, there is concern that the number of such incidents could increase.

So far, research was mostly conducted on the effects of cannabis products where cannabidiol (CBD) is the dominant compound, yet we still lack concrete research on the effects of tetrahydrocannabinol (THC) and its impact on pets. 

Nevertheless, what we do know is that it can cause a series of alarming symptoms, such as vomiting, diarrhea, difficulty walking, dribbling urine, as well as light and sound sensitivity. 

Still, cannabis itself is not lethal for dogs, said Sandler. Though, the issue appears when cannabis is combined with edibles that are widely known as toxic for dogs (e.g., a combination of chocolate and weed); the same is probably true for cats as well.

Apart from these unfortunate situations, cannabis is still being investigated as a means of treating various medical conditions in animals — the newest study launched at the University of Guelph is concerned with cannabis and bladder cancer in dogs. 

Despite this, vets are currently not allowed to legally prescribe medical cannabis for animal use, and there are no licensed products whatsoever. Though potential benefits do exist, it’s still a challenge for pet owners to dose cannabis to their animals properly.

So, if you’re a pet owner concerned about whether your pet might have ingested cannabis or not, the best course of action is to simply go to a vet who will induce vomiting and possibly administer an activated charcoal substance, which absorbs cannabis and alleviates its effects.