Pets and Marijuana

Pets and Marijuana,

Marijuana contains a psychoactive substance called tetrahydrocannabinol or THC.  This is the substance that gives humans a “high.” It is also the substance that makes marijuana toxic to pets.

Pets can be poisoned by marijuana in different ways: they can eat commercial or homemade edibles, such as baked goods or candies; or directly ingest marijuana or marijuana-related products (e.g.: oils, inhalers); or they can inhale it through second-hand smoke. Dogs and cats are far more sensitive to THC than humans and can have dramatic reactions to even a small amount.


Signs can occur anywhere from five minutes to four days after a pet is exposed. The signs may last several days, depending on the amount of marijuana ingested or the concentration of THC in the substance consumed.

Common signs include:

  • Lethargy
  • Overreaction to sounds
  • Dilated pupils or glassed-over eyes
  • Dazed expression
  • Difficulty walking
  • Vomiting

Other signs include:

  • Low or high heart rate
  • Whining or crying
  • Agitation
  • Increased or decreased body temperature
  • Incontinence/dribbling urine
  • Tremors
  • Seizures
  • Coma

Consuming a marijuana product with a higher concentration of THC or ingesting a large amount can result in seizures, coma, or death, especially in cats and small dogs.

If your pet ingests marijuana, contact your veterinarian, or call the ASPCA Animal Poison Control Center at (888) 426-4435 or Pet Poison Helpline at (855) 764-7661.

If your pet shows signs of wobbliness, incontinence, is hyper-reactive to sounds, has seizures, or is showing signs of hyperthermia such as excessive panting, you should take your pet to the nearest animal emergency hospital.


Diagnosis is based on the signs and a history of exposure, so it is important to be forthcoming with the information. Be as specific as possible when describing how your pet was exposed to marijuana, and how much was ingested. A dog who ate a marijuana brownie (a double toxicity because of the THC and chocolate!) will need a different treatment than a dog who inhaled too much smoke.


Although there is no antidote for marijuana toxicity, treatments can help counteract the clinical signs. Some common treatments include regulating the body temperature, administering fluids to maintain hydration, and giving injections to stop vomiting. Your pet’s heart rate also will be monitored to ensure that the rate and rhythm stay within normal ranges.

Most animals recover with treatment, however ingesting large amounts of marijuana can be fatal, especially in small dogs and cats.


Much like medication, it’s important to keep all forms of marijuana out of your pet’s reach, preferably in locked cabinets or drawers. Keep in mind that pets have a keen sense of smell and are likely to sniff out and eat candy, baked goods, and plants if they have access to them.

If marijuana is being smoked, keep your pet in a separate area with good ventilation — and secure screens on the windows — until the smoke has cleared.

Since the legalization of marijuana will likely lead to increased usage in public places, it’s important to look out for remnants of marijuana cigarettes (joints) or discarded edibles on the street or in the park.

By The Animal Medical Center