An ever-increasing number of households are using marijuana for recreational and medicinal purposes, which means that more pets are being exposed to this toxic plant. The ASPCA animal poison control center experienced a 700% increase in marijuara-related calls in 2019, and our animal emergency hospital has seen a similar increase. Pets are more likely to ingest marijuana-containing products, such as baked goods and candy, than the plant itself, and the growing variety of edibles has contributed to pet exposure. Although marijuana exposure rarely causes dangerous effects, toxicity should be taken seriously, and any exposed pet should always be examined by a veterinarian.

Why is marijuana toxic to pets?

Pure marijuana is made up of dried material from the Cannabis sativa plant, which contains more than 400 compounds, including more than 80 cannabinoids. Tetrahydrocannabinol (THC) and cannabidiol (CBD) are two commonly used cannabinoids, although only THC has psychotropic properties. CBD is believed to be relatively non-toxic to pets; however, THC may  cause moderate toxicity.

How are pets exposed to marijuana?

A large variety of THC-containing products are available that present many pet exposure opportunities, including: 

  • Dried cannabis plant material
  • Cannabis concentrates, such as kief, hash, or rosin
  • Edible products, including brownies, gummies, and THC butter
  • Marijuana smoke

In dogs, most exposures occur when they eat a THC-containing product, such as baked goods or candy, whereas cats seem to be attracted to the dried bud form. Ingesting an edible product that may contain additional toxic compounds, such as chocolate or the artificial sweetener xylitol, can also cause problems in pets. Be aware that cannabis concentrates contain more THC by volume, and therefore have higher toxicity potential. Second-hand marijuana smoke inhalation can also cause pet toxicity. 

How do I know if my pet has been exposed to marijuana?

Pets with marijuana toxicity exhibit clinical signs approximately 30 to 60 minutes after ingestion, or sooner after inhalation. Clinical signs, which are typically non-life-threatening, can include:

  • Lethargy
  • Glassy eyes
  • Dilated pupils
  • Incoordination
  • Stumbling
  • Urine dribbling
  • Agitation
  • Excitement
  • Vomiting
  • Tremors
  • Body temperature abnormalities

Serious effects from marijuana are rare, although they can occur if a pet ingests a large amount, or is exposed to a highly concentrated THC form. Heart rate abnormalities, seizures, coma, and death are possible in severe toxicity cases. Because THC is stored in the body’s fat, toxicity signs can last up to 36 hours after exposure. 

If your pet is exhibiting abnormal behaviors consistent with marijuana toxicity, she should be examined by your family veterinarian immediately. If exposure occurs outside your veterinarian’s normal hours, our animal emergency hospital is open from 5 p.m. to 8 a.m., Monday through Friday, and 24 hours a day during weekends and holidays. Although severe toxicity effects are rare, you must let a veterinarian determine whether your pet is in danger.

Can I be in trouble if my pet develops marijuana toxicity?

Since recreational and medicinal marijuana use is legal in Washington state, do not be concerned about your veterinarian reporting your pet’s toxicity. However, whether or not marijuana use is legal, a veterinarian’s top priority is identifying a pet’s toxicity so she can treat the pet appropriately, and she is not obligated to report owners to the police.

How is marijuana toxicity treated?

No antidote is available for marijuana toxicity, so care involves support to manage symptoms, and may include:

  • Emetics — Medications may be used to cause vomiting if ingestion was recent; however, marijuana can have anti-vomiting effects that may counteract these efforts.
  • Activated charcoal administration — Activated charcoal can be administered orally to bind to the toxin in the gastrointestinal tract and prevent its absorption into the bloodstream.
  • Intravenous (IV) fluids — Fluid administration maintains hydration and helps with toxin elimination.
  • Anti-vomiting medications — Marijuana can have anti-nausea effects, but may cause vomiting in some pets, which can be controlled with medications.
  • Blood pressure monitoring — Pets are monitored for blood pressure abnormalities that may result from marijuana’s cardiovascular effects.
  • Thermoregulation — Pets suffering from marijuana toxicity may have difficulty regulating their body temperature, so their temperature is monitored, and corrective measures taken if it falls outside the normal range.

How can I prevent marijuana toxicity in my pet?

If you have marijuana or THC products in your home, store them where your pet cannot access them, and dispose of all remnants in a secure trash can. If houseguests bring marijuana, warn them of the dangers to your pet and ask them to store it safely out of your pet’s reach, such as locked in their car. 

You must never treat your pet’s medical condition with marijuana, THC products, or CBD. Studies involving medical marijuana use in animals are sparse, and enough information is not currently available to establish proper dosages. Although marijuana use is legal in many states, no laws permitting human use extend to pets, and it is illegal for veterinarians to prescribe products containing THC or CBD.

If you have questions about marijuana toxicity, or if you think your pet may have been exposed, call your family veterinarian. If your primary hospital is closed, contact our animal emergency hospital for after-hours treatment.