Audra Stillabower, CVT
Veterinary Information Specialist

With its legalization in various states across the United States, marijuana is becoming very common in households for medicinal purposes. In fact, over the past 6 years, Pet Poison Helpline® has experienced a 448% increase in marijuana cases. Here’s what you should know about marijuana ingestion in pets.

Marijuana or Cannabis sativa/Cannabis indica is used for recreational drug use and for medicinal purposes. Tetrahydrocannabinol (THC) and cannabidiol (CBD) are the two most commonly recognized, utilized, and studied cannabinoids although there are over 80 different cannabinoids in marijuana plants.  The primary difference between the two is that THC causes psychotropic effects and has a moderate level of toxicity while CBD is non-psychotropic and is felt by many investigators to be non-toxic or have limited toxicity. The exact amount of each cannabinoid varies widely from strain to strain and plant to plant.

Cannabidiol is thought to have the following properties:  anxiolytic, antipsychotic, antiemetic, anti-seizure, and anti-inflammatory. Medically, THC is used in attempt to alleviate muscle spasms caused by multiple sclerosis, nausea from chemotherapy, weight loss in AIDS patients, seizure disorders and Crohn’s disease. Tetrahydrocannabinol is also used recreationally for its psychotropic effects.

Animals can be poisoned by marijuana in different ways. They can ingest marijuana edibles such as brownies or pot butter, ingest the owner’s supply of marijuana (in any formulation), or by second hand smoke. Common symptoms of marijuana toxicity include sedation/lethargy, dilated pupils or glassed over eyes, dazed expression, difficulty walking and vomiting. Other symptoms can include either a low or high heart rate, vocalization such as whining or crying, agitation, trouble regulating temperature causing the body temperature to drop or rise and incontinence/dribbling urine, tremors, seizures and potentially coma. Signs of toxicity can be seen anywhere from 5 minutes to 12 hours after the animal is exposed to marijuana. The signs can potentially last 30 minutes to several days depending on the dose ingested.

Although there is no true antidote for marijuana, veterinarians can give supportive care to help the pet through the clinical signs. Vets can regulate the temperature of the animal to ensure they aren’t too hot or cold and give fluids to help maintain hydration. They can give anti-vomiting medication to help stop fluid loss and closely monitor the animal’s heart rate to ensure that it is stable. Due to the animal having trouble walking and potentially injuring itself, the clinic staff can help keep the pet comfortable and confined so they won’t be injured. In a lot of cases, a veterinarian may give activated charcoal. This is a liquid that the animal drinks or is given that can help bind the toxin in the stomach or intestines to the charcoal and prevent absorption into the body.

Animals normally do well with supportive care, however large ingestions of marijuana can be dangerous. Common problems with diagnosing and treating marijuana cases in the veterinary clinic are due to incomplete history which could be due to drug stigma, the owners on vacation, pharmaceutical products or worries about legal repercussions. It is important to get a complete history and reassure owners that the clinic is only interested in providing appropriate medical care for their pet.  Accurate and complete medical history is imperative so that only necessary treatments are provided and prevent unnecessary treatments and costs.

With marijuana being legalized in many different states, there has been an increase since last year with many additional cases of poisonings reported. Getting accurate medical history is important in treating pets appropriately and without unnecessary treatments. Some tips for helping prevent toxicity include placing marijuana edibles well out of reach of the pet in closed high cabinets or in a locked drawer when not in use. If marijuana is being smoked, the pet should be kept in a separate area with good ventilation until the smoke has cleared. This will help prevent many of the marijuana poisonings from occurring.

If you find yourself in a medical emergency, call your veterinarian or Pet Poison Helpline® at 800-213-6680. We are available 24 hours a day, 7 days a week even on holidays to help with pet poison emergencies.