Avoid Tragedy: Be Alert to This Rising Poison Threat

dog marijuana poisoning

Story at-a-glance -

  • Hazel, a 3-year-old Labrador Retriever in California, provides us with a reminder that marijuana and dogs can be a toxic combination
  • With the increasing availability of marijuana in all its forms, and its higher potency, veterinary clinics and pet poison hotlines are seeing a tremendous increase in cases of marijuana intoxication
  • Classic signs of poisoning include glassy eyes, a dazed expression, slow response times, loss of coordination and dribbling urine; the more THC the dog ingests, the more severe the symptoms
  • Marijuana for humans contains much more THC than pets can safely consume; CBD oil for pets is made from hemp plants and contains very low levels of THC, which removes the risk of toxicity

By Dr. Karen Shaw Becker

A recent Facebook post by Dr. Jen Gunter of Marin County, California about her Labrador Retriever, Hazel, is a good reminder that marijuana and dogs can be a toxic combination. Gunter and 3-year-old Hazel went for their daily run, and then Gunter went grocery shopping. When she arrived home, she noticed immediately that something was wrong with Hazel.

“She was on the couch,” Gunter told NBC News. “Her head was hanging over and she couldn’t lift herself up. I got out the tennis ball, which she ignored. Normally, you get out the tennis ball and she is just all over it.”1

As soon as Gunter touched Hazel, the dog began to shudder. She couldn’t hold herself upright or even keep her eyes open, and then lost control of her bladder. Gunter, terrified, rushed Hazel to an emergency animal hospital, where the veterinary staff immediately suspected marijuana poisoning.

Sure enough, the dog’s urine toxicity test showed positive for THC (the psychoactive chemical in marijuana). Gunter suspects Hazel scarfed up part of an edible or a joint while they were out for their run. Her Facebook post urges people to properly store and discard marijuana products to protect pets.

Today’s Marijuana Is More Accessible, Comes in More Forms, and Is Much More Potent

A 2012 retrospective study (2005 to 2010) analyzed trends in marijuana toxicosis in dogs living in states with legalized medical marijuana.2 The researchers looked at 125 family dogs in Colorado that had been seen by a veterinarian at one of two veterinary hospitals for known or suspected marijuana poisoning.

Their results revealed a significant correlation between the number of medical marijuana licenses and marijuana toxicosis cases seen at the two hospitals. The majority of dogs recovered, but two dogs who ingested edibles made with medical-grade THC butter didn’t survive.

Fast-forward to 2018, and the emergency vet staff in California that treated Hazel sees 10 cases of marijuana poisonings a week, and they certainly aren’t alone. According to the American Veterinarian journal, vets across the U.S. are reporting a significant increase in the number of pets — mostly dogs — being treated for marijuana intoxication.

Both medical and recreational marijuana have become increasingly available in recent years, and in novel forms such as foods, pills, oils and tinctures. In addition, new hybrids and cultivation techniques have resulted in plants with significantly more THC than in decades past.

The Pet Poison Helpline reported a stunning 448 percent increase in calls for marijuana poisoning over the past six years, with the majority involving pets who ingested marijuana-laced food products.

Pets Can Ingest High Levels of THC in Any Number of Ways

From the Pet Poison Helpline:

“Cannabis sativa and cannabis indica are members of the Cannabaceae family. Slang terms include pot, weed, grass, and Mary Jane, just to name a few. Marijuana affects receptors in the brain which alter normal neurotransmitter function. Dogs and cats can be poisoned by marijuana from smoke exposure or from eating any type of marijuana/THC plant or laced baked foods (e.g., pot brownies, pot butter, etc.).

Other sources of THC include highly concentrated oil products, like butane hash oil (BHO or ‘dabs’), filtered and purified oil (‘shatter’), or wax made from whipped oil. These products are meant to be smoked via a bong (water pipe), or ‘vaped’ like e-cigarettes in order to give users an instantaneous, powerful high. All of them contain 60 [to] 90 [percent] THC, and small ingestions pose great risk for pets.”3

As veterinarian Dr. Gary Richter of Holistic Veterinary Care in Oakland, California explained to NBC News, dogs have more cannabinoid receptors than humans, which makes them more susceptible to the effects of cannabis than people.

Signs of Marijuana Poisoning

In dogs who’ve ingested marijuana, noticeable symptoms can appear within minutes to hours depending on the type of exposure (inhalation versus ingestion). Typical signs of poisoning include glassy eyes, a dazed expression, slow response times, loss of coordination and dribbling urine.

There can also be vomiting and drooling, seizures, changes in heart rate, decreased body temperature, low blood pressure, tremors, dilated pupils, vocalization, neurological stimulation, hyperactivity and coma. The more THC the dog ingests, the more severe the symptoms usually are.

Treatment is supportive in nature, and depending on the situation may include inducing vomiting and/or administering activated charcoal to minimize the amount of toxin absorbed by the body. For more serious cases, intravenous (IV) fluids may be given and respiration monitored.

Bottom line: Keep all marijuana plants and products stored safely away from pets, and when outdoors with your dog, stay alert for signs he’s picked up something in his mouth. Marijuana isn't the only drug dogs are being exposed to while out and about. If you know or suspect your dog has ingested marijuana, call your veterinarian, the nearest emergency animal hospital, or the Pet Poison Helpline at 855-764-7661 immediately.

Medical Marijuana for Humans Versus Medical Marijuana/Cannabidiol (CBD) for Pets: An Important Distinction

The legality of treating pets with cannabis products is still a muddle, but that issue aside, it’s important to understand the difference between medicinal marijuana for humans versus pets. It’s primarily about THC levels — humans can tolerate a significantly higher level of THC than is safe for pets.

Meanwhile, there’s an exploding cannabidiol market out there for pets (and people). CBD oil products approved for pets are made from hemp or cannabis plants that contain all the benefits of medical marijuana, but with low-to-undetectable levels of THC. There are also studies underway at some veterinary teaching hospitals and colleges to evaluate the effectiveness of CBD oil in treating a variety of conditions that occur in dogs and cats, including seizures and arthritis.

If you’re interested in learning more about CBD oil for your pet, be sure to consult with a reliable, reputable source. Ask for a “Certificate of Analysis” from the manufacturer that shows how much THC is in the product (it should never be over 0.3 percent), how it’s made, and whether it’s organic and free of pesticides and other chemicals.

I also recommend my friend Dr. Rob Silver’s book, “Medical Marijuana and Your Pet: The Definitive Guide.” It’s written for dog and cat owners to help them understand the benefits and risks of cannabidiol for pets, as well as regulatory issues.