Marijuana Toxicity in Dogs: Understanding Risks and Prevention

This pet health content was written by a veterinarian, Dr. Debora Lichtenberg, VMD. This article was originally published in 2014 and is regularly updated. It was last reviewed for accuracy and updated on July 9, 2024

If you have questions or concerns, call your vet, who is best equipped to ensure the health and well-being of your pet. This article is for informational purposes only and is not a substitute for professional medical advice, diagnosis or treatment. See additional information.

Rising Cases of Marijuana Toxicity in Dogs

As the movement to legalize and decriminalize marijuana has grown in recent years in the United States, marijuana toxicity in dogs has been on the rise. As of 2020, more than half of the states have passed laws to either fully or partially decriminalize possession offenses.

• From 2018 to 2019, the ASPCA’s Animal Poison Control Center reported a 765% increase in marijuana cases involving pets. This trend is nationwide.
• Sales of cannabis edibles have been shooting through the roof during the COVID-19 pandemic.

Understanding marijuana toxicity in dogs is more important than ever before. Here is what you need to know to keep your pets safe.

Marijuana Toxicity in Pets

In 2014, while running a rural veterinary practice, I encountered the worst emergency case of marijuana/chocolate toxicity in a dog I had ever seen.

My new little patient had multiple strikes against him:

• A small, 14-pound dog
• Had eaten a large amount of dark chocolate brownies
• The brownies were loaded with hashish
• His caretakers didn’t realize this until they found him comatose about 15 hours later

Even if his folks had not told me what he had gotten into, the little dog’s breath was a dead giveaway. He reeked of marijuana, which was the strongest pot smell I had ever detected on a dog.

The good news? The midnight brownie bandit recovered fully. He saved his own life by vomiting up a large amount of his hash bash, and then we supported him through his detox phase.

Understanding marijuana toxicity in dogs is crucial for their safety and well-being.

Here’s a quick video of my patient:

How Serious Is It If My Dog Ingests Marijuana?

Thankfully, veterinarians can usually relax and laugh — a little — when we see “a party animal” fall into our hospital. Marijuana has a “wide margin of safety,” meaning it takes a great deal of the substance to be lethal. “There’s nothing about that actual drug itself that will kill them,” says Dr. Dorrie Black, DVM, MPVM. “It doesn’t cause any organ failure. It doesn’t cause liver failure, renal failure.”

But that doesn’t mean it isn’t a serious concern. “Pets don’t get stoned — they get poisoned,” says Dr. Mark Liberto, DVM.

• In a few cases, small dogs have died after ingesting large quantities of food containing marijuana. If a dog eats an entire tray of brownies containing marijuana or hashish, the situation is potentially life-threatening. Even so, deaths are extremely rare cases where people have not been around to notice the emergency. These intoxicated dogs probably could have been saved with medical intervention and support.
• “There may be additional toxic ingredients involved — such as chocolate, raisins, or xylitol — which result in a poorer prognosis. Cats may also directly consume the plant material,” says the American Veterinary Medical Association (AVMA).
• Additionally, be aware that the drug can sedate a pet so fully that they end up inhaling their own vomit (aspiration), which can be deadly.

“If you know or suspect your pet of having been exposed to any form of cannabis, please consult your veterinarian immediately,” the AVMA advises.

Signs of Marijuana Poisoning in Dogs

If your dog ingests marijuana, you may notice some telltale signs:

• Dilated eyes
• Drunken appearance
• Stumbling

Sound familiar? If you are chilling with your dog, the pair of you will look just about the same. Your dog may also vomit, become agitated, or exhibit urinary incontinence or urine dribbling.

Here’s a deeper look at the signs of marijuana toxicity in dogs:

• Mydriasis: This term describes dilated pupils. Think of that glassy-eyed, dull but staring sort of look when someone is under the influence.
• Somnolent: This word is borrowed from human medicine when describing a patient with altered consciousness. Somnolent means the individual can be easily aroused but requires stimulation to stay awake. In other words, your stoned dog is continually nodding off. Somnolent is the state between lethargy and obtunded (unable to rouse).
• Head weaving at rest and listing to one side: Dogs under the influence of marijuana are rolling their heads around and listing to one side or the other when trying to walk (ataxia). In other words, they look like a cartoon drunken sailor.
• Dribbling urine: Unlike many other toxicoses, pot almost always makes a dog dribble urine uncontrollably. If we notice this, marijuana should be high on the list of suspects.

With any luck, you yourself are not in the same condition, so you can get your dog to the vet right away.

Diagnosing Marijuana Toxicity in Dogs

The intoxicated state of the dog is a key indicator of marijuana toxicity, but other serious toxins can create similar signs.

“As the attending veterinarian, I consider the possibility of other factors contributing to the overall picture of health or illness,” says Dr. Patrick Mahaney, VMD. “Did the dog consume only cannabis? Could prescription or over-the-counter human or veterinary medications, other recreational drugs, or unknown intoxicating substances be involved?”

Being completely up front and honest with your vet is crucial, but many people are too embarrassed to admit to marijuana exposure. “Most are somewhat reluctant to share the truth, but ultimately concede under gentle, direct questioning,” says Dr. Mahaney.

If the drug exposure is unknown, a quick toxicology screen can test for:

• Cocaine
• THC (the psychoactive ingredient in marijuana)
• Opiates
• Methamphetamines
• Benzodiazepines
• Oxycodone

Identifying the drug helps in treatment. If the dog tests positive for THC, it confirms marijuana exposure and aids in the appropriate medical response.

How Toxic Is Marijuana to My Dog, Really?

Officially speaking, there is no safe level of exposure for dogs. However, ingestion of marijuana by a dog is generally less dangerous compared to other drugs.

• Accidental Ingestion: Most dogs get into marijuana accidentally by finding bags of weed, partially smoked joints, gummies, or brownies and then binging on them.
• Deliberate Exposure: In rare and irresponsible cases, some individuals may deliberately get their dogs high. These individuals are unlikely to seek veterinary care for their intoxicated dogs.
• Honesty Helps Treatment: Being honest and knowledgeable about the amount and source of the drug can significantly help your vet with the treatment plan.

While marijuana toxicity in dogs is serious, it is relatively safer compared to other substances, provided that appropriate care is administered.

Treatment of Marijuana Toxicity in Dogs

The onset of symptoms after ingesting or inhaling marijuana is typically 30–60 minutes in dogs. Depending on the dosage and strength of the drug, these symptoms can last 18–36 hours.

If a dog is intoxicated, supportive care is all that can be provided as there is no antidote to reverse the effects of marijuana. Essentially, the dog has to sleep it off under supervision.

Treatment may include:

• Activated charcoal to absorb some of the toxins
• IV fluids for hydration and support
• Anti-vomiting medication to prevent further complications
• Temperature regulation to maintain normal body temperature
• Controlling seizures or tremors if they occur

“Having treated innumerable cannabis toxicities, I feel comfortable that my patients will make a full recovery with the appropriate care,” says Dr. Mahaney.

Consequences of Marijuana Toxicity in Dogs

Some clients are reluctant to “come clean” about their dog’s marijuana ingestion because they fear being reported to the police. However, veterinarians are not obligated to report your use or your dog’s marijuana use to authorities. “The veterinarian is not under obligation to report the owner/client to the police, and it is better for all involved to treat the animal appropriately,” says VRCC Veterinary Specialty and Emergency Hospital of Englewood, Colorado, a state that legalized recreational marijuana in 2014.

• No Obligation to Report: Veterinarians focus on treating the animal appropriately rather than reporting the incident.
• Animal Abuse Exception: Actual animal abuse is a different story, and veterinarians are responsible for reporting abuse. However, accidental marijuana ingestion does not qualify as abuse.

For more information on recognizing and addressing animal abuse, refer to this resource.

Another Case of Marijuana Toxicity in Dogs

A young person once brought her terrier mix to my veterinary clinic for staggering and exhibiting strange neurological behavior.

• Symptoms: The dog had dilated, glazed eyes and a strange walking pattern.
• Owner’s Observation: The owner insisted the dog couldn’t have gotten into anything, claiming, “We watch him like a hawk. He woke up like this.”

After about an hour, the dog seemed better. A walk revealed the dog was uncomfortable and eventually pooped out large cocktail almonds, improving significantly.

It’s likely the dog had ingested marijuana the night before and found snacks to satisfy his munchies. Within a few hours, he fully recovered.

Final Thoughts on Marijuana Toxicity in Dogs

Although marijuana has a large safety margin, it can still make your dog quite ill and neurologically impaired.

• Danger of Baked Goods: Baked goods laced with marijuana are particularly dangerous. While a human might have one or two brownies, a dog might eat the entire tray, leading to severe toxicity.
• Increased Availability: With more marijuana edibles available than ever, it’s crucial to keep them out of reach of your dogs.
• Visitor Caution: Be cautious with visitors. Even something as small as a piece of weed in a coat pocket could lead to an emergency vet visit if your dog gets into it.
• CBD Oils and Edibles: These are not completely safe either. There have been documented reports of dogs developing THC signs after ingesting CBD products. Be careful with these too (CBD oils).
• Medical Marijuana: This is a complicated topic among veterinarians. For more information, see the article “When Will Medical Marijuana Become Legal for Pets?”.

Frequently Asked Questions (FAQ)

References

• “Decriminalization: States With Marijuana Decriminalization Laws.” NORML. https://norml.org/laws/decriminalization/.
• “State Marijuana Laws.” Governing. https://www.governing.com/gov-data/safety-justice/state-marijuana-laws-map-medical-recreational.html.
• “Marijuana Toxicosis in Animals.” ASPCA Pro. https://www.aspcapro.org/resource/shelter-health-poison-control/marijuana-toxicosis-animals.
• Stine, Alison. “You Know What Else Sold Well During the Pandemic? Weed Edibles.” New York Times. July 13, 2020. https://www.nytimes.com/2020/07/13/style/weed-edibles-pandemic.html.
• Thometz, Kristen, and Paul Caine. “Pot Makes Pets Sick, Says Veterinary Group.” WTTW News. Jan. 21, 2020. https://news.wttw.com/2020/01/20/pot-makes-pets-sick-says-veterinary-group.
• Fletcher, Lisa. “Pet Poisoning From Marijuana on the Rise, Veterinarians Say.” WJLA. Jan. 31, 2019. https://wjla.com/features/7-on-your-side/pet-poisoning-from-marijuana-on-the-rise-say-veterinarians.
• “Cannabis Use and Pets.” American Veterinary Medical Association. https://www.avma.org/resources-tools/veterinarians-and-public-health/cannabis-use-and-pets.
• Klivans, Laura. “Legal Weed’s a Growing Danger to Dogs, So Keep Your Canine Out of Your Cannabis.” Kaiser Health News. June 21, 2019. https://khn.org/news/legal-weeds-a-growing-danger-to-dogs-so-keep-your-canine-out-of-your-cannabis/.
• Khan, Safdar A., DVM, PhD, DABVT. “Toxicities from Illicit and Abused Drugs.” Merck Veterinary Manual. 2014. https://www.merckvetmanual.com/toxicology/toxicities-from-human-drugs/toxicities-from-illicit-and-abused-drugs.
• Mahaney, Patrick, VMD. “Treating Marijuana Toxicity.” Veterinary Practice News. July 13, 2011. https://www.veterinarypracticenews.com/treating-marijuana-toxicity/.
• Gollakner, Rania, DVM, and Lynn Buzhardt, DVM. “Cannabis (Marijuana) Intoxication in Cats and Dogs.” VCA Hospitals. https://vcahospitals.com/know-your-pet/marijuana-intoxication-in-dogs-and-cats.
• Freed, Erin, CVT, BAS. “Illicit Drugs: What Veterinary Nurses Need to Know.” Today’s Veterinary Nurse. 2019. https://todaysveterinarynurse.com/articles/illicit-drugs-what-veterinary-nurses-need-to-know/.