Is Medical Marijuana Safe for Pets? A Case for More Study

Dogs are most commonly exposed to cannabis through THC-laced edibles they find in the trash or in other opportune places, though some may ingest marijuana through purposeful exposure by their owners to tinctures, vapors and even homemade dog biscuits. The incidence of both intentional and unintended exposure is increasing as legalization spreads throughout the United States. As a cautionary tale, veterinary hospitals in Colorado have witnessed growing numbers of animals admitted for marijuana poisoning. Even before laws passed in Colorado allowing sales for recreational purposes, the number of dogs presenting with marijuana toxicosis quadrupled. Contributing factors beyond increased availability likely include a higher awareness among clinicians of the signs of poisoning, population shifts (e.g., marijuana “tourism” and immigration) and a greater willingness of clients to seek veterinary assistance for the condition.

Depending on the dose and route of administration, problems usually appear within 30 to 60 minutes after exposure. The ASPCA’s Pet Poison Helpline lists 12 common signs of toxicity ranging from coma to seizures and respiratory depression to hyperactivity.

Calls for Caution

Much more needs to be done to make marijuana safe not only for pets but for humans, too. To both pets and people, marijuana-laced foodstuffs are indistinguishable from their innocuous counterparts, raising the risk of accidental ingestion by children, animals and unsuspecting adults. The amount of THC cooked into the cookies, chocolates and other foods can also take those intentionally consuming the products by surprise. For example, shortly after consuming a marijuana cookie, a college student jumped to his death from a motel balcony. In another case, a Denver man shot and killed his wife after supposedly eating cannabis candy.

Those incidents underscore the urgent need for education, regulation and research. Unfortunately, federal restrictions on marijuana research have hampered investigation into both its value and dangers. Decade after decade, advocates of less restrictive marijuana laws have unsuccessfully petitioned the Drug Enforcement Administration (DEA) to rethink the listing of marijuana as a Schedule I addictive drug with no therapeutic value. Delisting cannabis would ease research restrictions and allow studies on safety and efficacy to move forward.

Today, inadequate oversight of the amount of THC that producers are putting into each serving of edible marijuana is resulting in injuries, as is the lack of guidelines for and availability of testing, labeling and protective packaging. Consumers are confused about how much to eat and whether one batch of cookies or candies will produce the same effects as the next, turning self-medicating into a game of wild guessing.

Safety Requires Study

As a result, Colorado is earning the reputation as the Wild West of medical marijuana. Tying the hands of researchers and clinicians who desperately want to begin research is federal law that bars them from studying the safety and effectiveness of medical marijuana. That is putting the safety of people, pets and the public in jeopardy. The cure? Remove restrictions on research so that scientists, physicians and veterinarians can study cannabis carefully and without risking their licenses, federal funding and/or freedom through imprisonment. Only then will we be able to safely determine the benefits and appropriate uses of medical marijuana for veterinary patients.

More on


Join the Conversation

Like this article? Have a point of view to share? Let us know!