My Dog Ate Weed: What to Do and When to Worry

If your dog ate marijuana in any form, the most important step is to call your veterinarian or an animal poison control hotline right away. Most dogs that receive supportive care recover fully, but cannabis can produce alarming neurological symptoms, and certain edible products carry additional dangers that make veterinary guidance essential. How quickly you act, and how honest you are with the vet about what your dog consumed, makes a real difference in outcome.

What Cannabis Toxicosis Looks Like in Dogs

Dogs process THC differently than people do, and the signs tend to look strange and frightening to owners who have never seen them before. A survey of veterinarians across North America found that the most commonly reported clinical signs included urinary incontinence, disorientation, loss of coordination (ataxia), lethargy, exaggerated sensitivity to touch or sound, and a slow heart rate.¹ Many dogs will also drool, vomit, or startle at sounds that would normally not bother them.

The combination of unsteady walking, dribbling urine, and seeming “out of it” is fairly characteristic. Some dogs become profoundly sedated, lying still and barely responding, while others become agitated and hypersensitive to stimulation. Both presentations fall within the expected range. Dogs can also develop dilated pupils, low body temperature, or, less commonly, tremors. The severity depends largely on how much THC was consumed relative to the dog’s size and whether the product contained other toxic ingredients.

Onset can vary. Research on THC absorption in dogs shows that a fasted dog absorbs THC faster, reaching peak blood levels in a little over an hour, while a dog that recently ate may not peak for several hours.² That means you might not see symptoms immediately after ingestion. If you know or suspect your dog ate weed, do not wait for signs to appear before calling the vet.

What to Do Right Away

First, try to figure out what and how much your dog consumed. Was it dried flower, an edible gummy, a THC oil cartridge, a discarded joint from the sidewalk? If there is packaging, bring it with you or photograph the ingredient list. The type of product matters because edibles often contain additional ingredients that are independently dangerous to dogs.

Call your regular veterinarian. If the clinic is closed, contact an emergency animal hospital or the ASPCA Animal Poison Control Center (888-426-4435) or Pet Poison Helpline (855-764-7661). These services can walk you through triage and tell you whether you need to come in immediately or can monitor at home. There is usually a consultation fee for the hotlines, but the guidance is specific and often saves unnecessary emergency visits or, conversely, catches cases that truly need intervention.

Do not try to induce vomiting at home unless specifically instructed to do so by a veterinarian. Cannabis has antiemetic properties, so inducing vomiting often does not work well once THC has begun to take effect. More critically, a dog that is already disoriented or sedated can aspirate vomit into its lungs, which creates a much more serious problem than the cannabis itself. If ingestion happened in the last few minutes and your dog is still acting normal, a vet may instruct you to induce vomiting, but that call needs to come from a professional who can assess the situation.

While waiting for veterinary guidance, keep your dog in a quiet, dimly lit space. If the dog is wobbly, prevent access to stairs or elevated surfaces. Monitor breathing and try to keep the dog warm if it seems cold. Note the time of ingestion if you know it, and any symptoms as they develop, so you can relay that information accurately.

When It Becomes an Emergency

Straightforward marijuana ingestion rarely kills dogs, and a review of 213 cases of cannabis toxicosis found that all dogs who received follow-up care made full recoveries.³ That is reassuring, but it assumes the dog got appropriate supportive care and that the product ingested was actually just cannabis.

There are several situations where the risk escalates and you should treat it as an emergency rather than a wait-and-see:

Very small dogs: A ten-pound dog eating a potent edible gets a far higher dose per pound of body weight than a seventy-pound Labrador eating the same thing. Small dogs can become dangerously sedated, with breathing that becomes shallow or slow enough to require monitoring.
Edibles with chocolate or xylitol: Chocolate is toxic to dogs on its own, and many cannabis edibles, especially brownies or chocolate bars, contain enough to cause separate poisoning. Xylitol (a sugar substitute also called birch sugar, increasingly common in gummies and candies) can trigger a rapid, life-threatening drop in blood sugar and liver failure in dogs. These secondary ingredients can be more dangerous than the THC.
Unknown substances: If you did not see the ingestion and are guessing based on symptoms, or if the product could be a synthetic cannabinoid rather than natural marijuana, the risk profile changes dramatically.
Severe symptoms: Seizures, extreme lethargy where the dog cannot be roused, very slow breathing, or a very slow heart rate warrant immediate veterinary attention. These are uncommon with simple marijuana but can occur at high doses or when other substances are involved.

The chocolate issue deserves extra emphasis. Marijuana-containing foods, many of which also contain chocolate, are the most common source of accidental THC exposure reported to Pet Poison Helpline.⁴ When a dog eats a cannabis brownie, the vet is dealing with two poisonings at once. Be sure to mention any non-cannabis ingredients in the product when you call.

What Happens at the Veterinary Clinic

There is no antidote for THC. Treatment is supportive, meaning the veterinary team manages symptoms and keeps the dog safe while the drug works through its system. In the 213-case review, management consisted of decontamination, sedation when needed, intravenous fluid therapy, temperature regulation, and general supportive care.³

Decontamination usually means inducing vomiting if the ingestion was recent enough and the dog is still alert, sometimes followed by activated charcoal to reduce further absorption. IV fluids help maintain blood pressure and hydration, and warming blankets or cooling measures address any body temperature abnormalities. If the dog is extremely agitated, mild sedation keeps it from injuring itself.

For more severe cases, some veterinarians have used intravenous lipid emulsion therapy. Because THC is highly fat-soluble, infusing a lipid solution can help bind the drug and reduce its effects.⁵ This treatment is not always necessary, but in cases of high-dose ingestion or when a dog is profoundly obtunded, it can shorten recovery time.

Most dogs start to improve within a few hours, though some take 24 to 72 hours to return fully to normal, depending on the dose. The vet may keep a mildly affected dog for a few hours of observation and then send it home, or hospitalize a more severely affected dog overnight.

Why Home Drug Tests Do Not Work on Dogs

Some owners, either out of curiosity or because they want confirmation before going to the vet, try using an over-the-counter human urine drug test on their dog. This almost never works. A study specifically testing this found that 20 out of 21 urine samples from dogs with confirmed marijuana toxicosis came back negative on a standard urine drug screen.⁶ The reason is that dogs excrete THC metabolites differently than humans do, producing very low concentrations of the specific metabolite those tests are designed to detect.

The same study found that all serum (blood) samples from those dogs did contain measurable THC when tested with a more sensitive laboratory method. So blood testing at a veterinary lab can confirm exposure, but the strip tests you buy at a pharmacy are not useful for dogs. In practice, most vets diagnose cannabis toxicosis based on clinical signs and the owner’s report rather than waiting for lab results, because treatment needs to start before results come back anyway.

Synthetic Cannabinoids Are a Different Problem

If your dog got into a product labeled as “K2,” “Spice,” or any of the many other names for synthetic cannabinoid compounds, the situation is more serious than natural marijuana exposure. A case report in the veterinary emergency literature noted that synthetic cannabinoid ingestion may cause more severe clinical signs than marijuana in dogs, and significant medical intervention may be necessary.⁷

Synthetic cannabinoids are not actually marijuana. They are lab-made chemicals sprayed onto plant material, and they bind to the same receptors in the brain but often with much greater intensity and unpredictability. In humans, these products have caused seizures, kidney damage, and deaths. In dogs, the toxicity profile is less well-documented simply because there are fewer published cases, but the available evidence suggests the clinical picture can be rougher, with more pronounced neurological signs and a greater need for intensive care. Intravenous lipid emulsion therapy has also been used in these cases because synthetic cannabinoids, like THC, are highly fat-soluble.⁷

The practical takeaway is that if you even suspect a synthetic product was involved, skip the phone triage and go directly to the nearest emergency veterinary hospital. The margin for error is smaller.

Why Cases Keep Climbing

Cannabis toxicosis in pets has become far more common in recent years, and the trend closely tracks the expansion of legal marijuana. A study analyzing poison control data from 2009 to 2014 found that dogs living in states where cannabis possession was legal or medically permitted had higher odds of a cannabis poisoning event compared to dogs in states where possession was fully restricted.⁸ Since 2014, many more states have legalized cannabis, and the legal market has exploded with edible products that are attractive to dogs because they look and smell like food.

The rise in edibles is the central driver. A dog is unlikely to eat enough dried marijuana flower to become severely ill because the taste is unpleasant. But a THC-infused peanut butter cup, gummy bear, or chocolate bar? A dog will eat the whole bag before you notice it is missing. The increasing potency of modern cannabis products also matters. THC concentrations in edibles and concentrates are far higher than in the marijuana plant material of previous decades, so a small amount of product can deliver a large dose.

This trend is worth keeping in mind even if you do not use cannabis yourself. Dogs encounter discarded joints and edible wrappers on sidewalks, in parks, and at beaches. They visit friends’ houses where products may be left on low tables. The “my dog ate weed” scenario does not require anyone in your household to use cannabis.

Be Honest With Your Vet

A significant barrier to effective treatment is owner reluctance to disclose what the dog actually ate. People worry about legal consequences or moral judgment. This is understandable but unnecessary and potentially harmful to the dog. Veterinarians are focused on treating the animal, not reporting you to anyone. Knowing the substance and approximate amount ingested lets the vet skip a lengthy and expensive diagnostic workup to rule out other causes like antifreeze poisoning, which can present similarly but requires completely different treatment.

Interestingly, many veterinarians themselves feel they lack clear guidance on cannabis-related issues. A survey of US veterinarians found that practitioners felt their state veterinary associations and veterinary boards did not provide sufficient guidance for them to practice within applicable cannabis laws.⁹ The regulatory landscape around cannabis and pets is murky, and vets are navigating it alongside their clients. The upshot: your vet is not the cannabis police and is genuinely just trying to help your dog.

CBD Products and Dogs

Some owners wonder whether the incident might actually be fine because the product was “just CBD.” Pure CBD (cannabidiol) does not produce the same intoxicating effects as THC, and research into CBD for pets is growing. However, there are currently no licensed veterinary CBD products on the market, and the regulatory and safety standards around these products remain underdeveloped.¹⁰ Many products marketed as CBD actually contain measurable amounts of THC, sometimes enough to affect a small dog. Label accuracy in the consumer CBD market is notoriously poor, with studies consistently finding that a substantial fraction of products contain more or less CBD than advertised, and some contain THC that is not disclosed on the label.

If your dog ate a CBD product, it is still worth calling the vet, especially for small dogs or if you are unsure of the product’s actual contents. The vet can assess based on the dog’s weight, the product details, and whether any symptoms develop. A high-quality, genuinely THC-free CBD product eaten in a small amount by a large dog is probably a non-event. A cheap, poorly labeled CBD oil eaten by a five-pound Chihuahua is a different story.

Dogs Versus Other Pets

Dogs account for the overwhelming majority of cannabis toxicosis cases reported to veterinarians and poison control, partly because dogs are more likely than cats to gobble down an entire edible they find lying around. Cats are more discriminating eaters in general, though they can still be exposed through secondhand smoke or by grooming a substance off their fur. Dogs can also be exposed through inhalation of smoke, which is sometimes overlooked as a route.³ If you smoke cannabis indoors or in an enclosed space with your dog, the dog can absorb enough THC to show clinical signs without ever eating anything.

For dog owners who also use cannabis at home, the simplest prevention is treating THC products with the same caution you would give medications or cleaning supplies: stored in closed containers, on high shelves or in locked drawers, and never left unattended where a dog can reach them. Edibles in particular should be treated like they are both tempting and dangerous, because to a dog, they are exactly that.

1
PLoS ONE. Prevalence and characteristics of cannabis-induced toxicoses in pets: Results from a survey of veterinarians in North America
2
PubMed. Pharmacokinetics of Bedrocan®, a cannabis oil extract, in fasting and fed dogs: An explorative study
3
Veterinary and Human Toxicology. Two hundred and thirteen cases of marijuana toxicoses in dogs
4
Veterinary Clinics: Small Animal Practice. Veterinary Clinics: Small Animal Practice
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PubMed. Marijuana poisoning
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PubMed Central. Detecting and quantifying marijuana metabolites in serum and urine of 19 dogs affected by marijuana toxicity
7
PubMed. Suspected synthetic cannabinoid toxicosis in a dog
8
PLoS ONE. The impact of state cannabis legislation, county-level socioeconomic and dog-level characteristics on reported cannabis poisonings of companion dogs in the USA (2009–2014)
9
PubMed Central. US Veterinarians’ Knowledge, Experience, and Perception Regarding the Use of Cannabidiol for Canine Medical Conditions
10
PubMed Central. CBD for pets: navigating quality assurance, safety standards, and marketing strategies