Marijuana Use in Pets: Toxicity or Therapy?

By Megan M. Kelley, DVM, CVA, CVSMT

With the legalization of recreational marijuana in Washington in 2012 veterinarians have seen a rise in marijuana exposure and intoxication in pets. Cannabinoids are the active chemicals found in hemp and marijuana plants and have a variety of effects. However, it is the psychoactive chemical, delta 9-tetrahydrocannabinol (THC), that causes the negative side-effects seen in pets. This includes incoordination, dilated pupils, slow heart rate, a characteristic startle reaction and sometimes urinary incontinence. THC loves fat, so it can be stored in the body’s fat deposits resulting in symptoms that can sometimes last for several days. Another cannabinoid chemical that is getting spotlight is Cannabidiol (CBD), which is more medicinal in nature and does not have the psychotropic effects of THC. This compound has been used in humans to treat seizures, decrease anxiety, improved appetite, and decrease nausea.

Marijuana exposure in pets can now come in many forms. In the past the typical history was of a dog eating a stash of marijuana or even the left over buds from joints. However, times are changing and pot use is evolving as people find inventive ways to distill out the THC. There are different strains of pot with differing levels of THC. Pot butter is an example of THC at its worst for pets. THC is fat soluble, which means it dissolves in fat. The fat in the butter leeches out and concentrates the THC. When pets eat these baked goods the high level of THC can cause all the signs listed previously and sometimes worse. Without proper care, pet’s body temperature and blood pressure can drop and in severe toxicity cases pets can stop breathing resulting in death.

Treatment for marijuana toxicity depends on the severity of the case. It is safest to have your veterinarian exam your pet and decide if decontamination is needed. This includes attempting to induce vomiting if the pet is stable enough, fluid therapy to flush out the system and activated charcoal as a binding agent for anything left within the stomach/intestines. In life threatening cases, veterinarians are also using concentrated fat solutions intravenously to attempt to bind the THC within the blood stream and flush it out.

So does that mean marijuana should not be used to treat medical conditions in pets? That is difficult for veterinarians to answer at this time since it is still illegal for veterinarians to prescribe or even recommend marijuana to treat patients. There are a lot of unanswered questions because of lack of research in pets due to legal restrictions and lack of funding.

What about CBD? Seattle-based companies like Canna Companion and Canna-pet are selling CBD products to treat pain and other medical problems for use in pets. These products don’t contain TCH, so the idea is the pets can get pain relief without getting high. These products are considered nutraceuticals and are not regulated by the FDA. The industry lacks uniform standards though, meaning a product marketed to have CBD or other cannabinoids may or may not actually contain those ingredients.

In the end, there is more unknown than known for both medical use of marijuana and accidental intoxications. What would help both veterinarians and owners make more informed decisions would be more information. This includes more studies and more experiments. Most veterinarians will continue treating pain, seizures and nausea in a traditional fashion at this time due to legalities. However, as veterinarian criticalist Tony Johnson said, “The winds of change are blowing, and there’s a faint smell of smoke on them.”