The increased accessibility to Cannabis (marijuana) has led to an increase in accidental exposure in pets.
While cannabis use is not new, its use for recreational purposes is more recent. In the 1970s,
cannabis was criminalized in the US when it was labeled a Schedule 1 (Class I) drug. In the 1990s, individual states began legalizing cannabis for medicinal use, and more recently, 9 states have legalized it for recreational use. Legalization for recreational use in Canada occurred in 2018. As with any other medication, the increased accessibility to the drug has led to an increase in accidental exposure in pets.
Cannabis contains more than 100 different chemicals (or compounds) called cannabinoids. Tetrahydrocannabinol (THC) is the cannabinoid that has the most psychoactive effects. It is also the compound responsible for some of cannabis’ medicinal uses, such as treating nausea and improving appetite in cancer patients. Other compounds, such as cannabidiol (CBD), have shown promise for medicinal use and do not have psychoactive effects.
Cats and dogs can become intoxicated by cannabis in various ways but the most common is eating baked goods, candies, cookies or getting hold of cannabis directly in any form. It is usually by accident and curiosity that causes intoxication in pets. Because dogs have more cannabinoid receptors in their brain they are also at risk of inhaling smoke when humans are smoking joints or vaping in the same room. A small amount of cannabis, relative to what a human can consume, is all it takes to cause toxicity in cats and dogs.
Regardless of the method of exposure, accurate and complete information is imperative to treating the animal successfully. For example, ingestion of a ‘pot brownie’ needs different treatment than inhalation, because eating the brownie requires treatment for cannabis and chocolate toxicity, whereas inhalation may require additional treatment for respiratory irritation. Like most drugs, the effects of cannabis are based on chemistry.
Biologically, the pet needs to excrete the toxin to rid its body of the poison. The THC component of cannabis is lipid-soluble, which means that it is easily stored in the fatty tissue in the liver, brain, and kidneys before being eliminated from the body. Cannabis needs to be metabolized through the organs and then excreted through the kidneys or bowels for the effect to wear off. All pets do not follow a single pattern of intoxication so a small amount may affect each dog and cat differently. There is not enough information to determine an official safe level or exposure, nor how age, health and body size determine the level of toxicity.
If you suspect your pet may have ingested THC signs of intoxication can include hyperactivity, loss of coordination, disorientation, pupils may dilate with excessive drooling or vomiting. In severe cases the pet may have tremors, seizures or fall into a coma. Side effects are usually short lived but an elevated heart rate and blood pressure could seriously endanger a dog or cat who has health issues before consumption.
As with all drugs in your home keep all cannabis-based products out of reach of your pet. Dogs and cats have a hard time resisting temptation and it is better not to present the opportunity for consumption.