Marijuana Exposure in Pets: Signs, Diagnosis, and Treatment
Sat, April 17, 2021

Marijuana Exposure in Pets: Signs, Diagnosis, and Treatment

Marijuana or cannabis has been used in the past as herbal medicine. Today, few countries allow it not just for medical use but also for recreation / Photo by: stokkete via 123RF


Marijuana or cannabis has been used in the past as herbal medicine. Today, few countries allow it not just for medical use but also for recreation. Growers are required to obtain a license from their federal government to determine how the products are sold and distributed. However, with increased accessibility to cannabis comes an increased risk of accidental exposure in dogs and cats.

How Pets Are Intoxicated

According to VCA Animal Hospitals, with branches in the US and Canada, pets can be intoxicated by cannabis in different ways. This includes eating edibles that contain cannabis, inhaling the second-hand smoke, or ingesting it directly. Most pet intoxication cases are accidental as pets are naturally curious about whatever's in their room. Compared to cats, canines have more cannabis receptors in their brains, which is why the effects are potentially more dramatic and toxic to them. Nevertheless, a little amount of marijuana is already enough to cause toxicity in both cats and dogs.

Regardless of how the pets are exposed to marijuana, complete and accurate information by the pet owners is necessary to treat animals successfully. For instance, the vet has to know if the dog ate a pot brownie. This requires a different treatment than pets who inhaled marijuana through smoke. Inhalation may need additional treatment because their respiratory system may have been irritated.

The University of Illinois Veterinary Teaching Hospital also shared via Illinois-based news provider News-Gazette that marijuana exposure in pets is likely to increase. They said that the animal poison-control hotlines in their area reported increasing numbers of calls relating to dogs or cats being exposed to marijuana ever since the drug was legalized for recreational and medical use in states in different parts of the country.

Veterinary emergency and critical care specialist Dr. Caroline Tonozzi, who heads an animal ER at the teaching hospital, said the rise in the number of intoxicated pets also indicates that more owners are more willing to seek medical attention for their four-legged friends.

Signs of Cannabis Intoxication

Dogs are likely to be intoxicated by ingesting the drug while cats are sickened by exposure to cannabis smoke. Both dogs and cats can be poisoned by exposure to tetrahydrocannabinol (THC), which is a substance found in cannabis.

Signs of cannabis intoxication in dogs include being less alert, drooling, general unsteadiness or swaying, and dribbling urine. On the other hand, cats will show symptoms that appear like a neurologic disease. This includes reacting to a visual stimulus that is not present and dilated pupils. Tonozzi added that there is a small number of reported deaths in canines because of marijuana exposure. However, there is increasing concern of co-intoxications from eating edible products, particularly those made with oil or butter that contains THC.

Aside from cannabis, some common poisons in dogs include chocolate, human drugs, anticoagulant rat poison, slug pellets, grapes and raisins, vitamin D, and onions. Common signs vary, depending on the product or food the dog consumed. For instance, eating chocolate may cause tremors, agitation, heart issues, and convulsions. On the other hand, accidentally eating human drugs may cause kidney failure, diarrhea, or sickness in dogs. Grapes and raisins may also cause kidney failure while slug pellets may cause unsteady feet, breathing problems, and convulsions.

Cannabidiol (CBD) is another compound found in marijuana but is not psychoactive, which means that it does not produce the kind of “high” that is linked with cannabis. Some health claims suggest that CBD is used for human patients and pets but Tonozzi warned that there is little science to support the effectiveness of CBD. The lack of regulation is also alarming. Studies show that some commercially available products that contain the compound had much lower or higher concentrations than what is identified on the product label.

The Illinois team is now joining forces with Kansas State University researchers to validate a test for cannabis exposure in animals that utilizes a mass spectroscopy analytic technique. Although the result will not provide a negative or positive finding, it will show a level of accuracy on the exposure of pets to marijuana. The currently available medical tests to detect cannabis in the body were created only for humans and are not reliable if used in pets. For instance, human urine tests may result in false negatives if used on dogs. Also, a blood test takes a long time and is not ideal to be used in pets that need immediate treatment.

Prevention is still the best cure, the Illinois authors said. Just like how pet owners keep their medication hidden, they should do the same thing to their marijuana if its use is legal in their country. Dogs and cats should not be allowed to enter a room with marijuana smoke or with food that contains pot or other non-pet-friendly ingredients.


Veterinarians are trained to evaluate a pet suspected of being intoxicated to make sure that the cause of intoxication is marijuana exposure. Treatment considerations for the pet include possible co-intoxication from foods that contain high-fat substances, raisins, xylitol, or chocolate. The animal will also be assessed to determine the type of care it needs, such as decontamination.

Tonozzi explains that some pets can go into a coma only within a few hours after marijuana exposure, which is why it is very important to have the pet evaluated right after exposure or ingestion. The vet might also advise the pet to be confined to the veterinary facility for ongoing monitoring.

Most Common Treats Given to Pet Dogs

In 2018, the most common types of treats given to pet dogs by their owners in the United Kingdom were the following: dog biscuit treats (76%), dental chews (63%), leftovers (27%), rawhide chews (25%), bones (19%), cheese (19%), roast dinner (11%), milk (5%), takeaway food (3%), human chocolate (2%), and grapes (1%). Even though chocolate is poisonous for dogs, there were still several respondents who stated that they were feeding their dogs human chocolate.

Meanwhile, the nonprofit organization American Society for the Prevention of Cruelty to Animal (ASPCA) shared the top 10 pet toxins n 2018. Over the counter medications, including cold medications, herbal supplements, naproxen, and ibuprofen, topped the list. It was followed by human prescription medications (antidepressants, ADHD medications, and heart medications, food (grapes, raisins, garlic, onion, and xylitol), chocolate (candy and baked goods), veterinary products, household items (paint, cleaning, and glue products), rodenticide (rodent baits), insecticide (ant baits, yard products, and bug sprays), plants (indoor, outdoor, and bouquets), and garden products (fertilizers, soil enhancements, and herbicides).

The bottom line is owners must protect their pets from poisonous substances, including marijuana, at all times.  Always be careful and remember that pets have a good sense of smell. Place things that are potentially toxic to animals in locked drawers or high cabinets.