A dog that has consumed marijuana will typically show a distinctive combination of signs: unsteady, wobbly walking, extreme sensitivity to touch or sound, dribbling urine, and an unusual level of sedation or spaciness. These signs can appear within minutes if the dog inhaled secondhand smoke, or take several hours to show up after eating an edible or flower. Most dogs recover within 72 hours, but some cases are serious enough to need emergency veterinary care.
The Most Common Signs
In a study of 223 dogs with confirmed marijuana exposure, the five most frequently documented symptoms were:
- Wobbly, uncoordinated movement (88% of cases)
- Exaggerated reactions to touch, sound, or light (75%)
- Unusual sleepiness or a “zoned out” look (63%)
- Dribbling urine without realizing it (46%)
- Vomiting (26%)
The wobbliness is often the first thing owners notice. Your dog may stumble, sway while standing still, or have trouble getting up from a lying position. It can look a lot like the dog is drunk. The exaggerated startle response is another telltale sign: a dog that normally ignores household noise may flinch, yelp, or jump at a door closing or someone speaking nearby.
Some dogs go the opposite direction and become agitated, anxious, or hyperactive. About 12% of dogs in the same study showed clear anxiety or restlessness, and roughly 7% had what the researchers described as “zoomies” or excitable, hyperactive behavior. A small number vocalized, whining or barking in ways their owners hadn’t seen before. This range of reactions, from deeply sedated to wired and anxious, can make it confusing if you’re not sure what your dog got into.
How Quickly Symptoms Appear
The timeline depends entirely on how the dog was exposed. If your dog was in a room with heavy marijuana smoke, signs can start within minutes. If the dog ate an edible, a piece of a cannabis plant, or a discarded joint, it can take one to three hours for symptoms to develop, sometimes longer. This delay happens because THC absorbed through the gut takes time to reach the bloodstream and brain.
The delayed onset with edibles is important to keep in mind. If you suspect your dog ate something an hour ago and seems fine, that doesn’t mean you’re in the clear. Keep watching for changes in coordination, responsiveness, and behavior over the next few hours.
When It Becomes an Emergency
Most marijuana exposures in dogs are uncomfortable but not life-threatening. The lethal oral dose of THC for dogs is over 3 grams per kilogram of body weight, which is an enormous amount relative to what’s in a typical edible or joint. Deaths from THC alone are extremely rare.
That said, severe cases do happen, and certain signs should prompt an immediate trip to the vet. A dog that becomes unresponsive or comatose, has seizures, breathes very slowly or shallowly, or loses the ability to swallow (you can sometimes tell because they drool without swallowing) needs professional care. These dogs may require breathing support and medications to stop seizures.
The bigger hidden danger comes from what else was in the product your dog ate. Marijuana edibles frequently contain chocolate, which is toxic to dogs on its own. Some edibles and cannabis gummies are sweetened with xylitol (now sometimes labeled as birch sugar), which can cause a life-threatening drop in blood sugar and liver failure in dogs. If your dog ate an edible, figuring out the other ingredients matters just as much as the THC exposure.
What Your Vet Can (and Can’t) Test For
You might assume a vet can simply run a drug test. It’s not quite that straightforward. Research has shown that standard human urine drug test kits, the kind you can buy at a pharmacy, do not reliably detect marijuana in dog urine. The same study found those kits worked well for other substances like barbiturates and opiates in dogs, but marijuana was a notable failure. Your vet will most likely diagnose THC exposure based on the combination of symptoms and your honesty about what the dog may have gotten into.
Being straightforward with your vet is genuinely important here. Veterinarians aren’t going to judge you or report you. They need accurate information to rule out other causes of neurological symptoms, some of which (like antifreeze poisoning or a brain problem) require very different and more urgent treatment. Telling them “my dog may have eaten a marijuana edible” saves time and could save your dog unnecessary tests.
What Recovery Looks Like
Most dogs are treated as outpatients, meaning they go home the same day. In a large survey of veterinarians across North America, the majority of marijuana-exposed pets were sent home with monitoring instructions, and those that were hospitalized typically stayed less than 48 hours. Full recovery usually happens within 72 hours.
During that window, your dog may continue to seem “off.” Expect lingering wobbliness, sleepiness, and possibly continued urine dribbling for a day or two. Keep your dog in a quiet, comfortable space away from stairs (the lack of coordination makes falls a real risk), make sure fresh water is available, and minimize loud noises or sudden movements that could trigger a startle reaction.
If your dog vomited early on, hold off on food for a few hours, then offer a small, bland meal. Dogs that are deeply sedated may not want to eat at all for 12 to 24 hours, which is normal as long as they’re still responsive when you gently try to rouse them. A dog that you truly cannot wake up, or that seems to be getting worse rather than better after several hours, needs veterinary attention.
Why Dogs Are More Sensitive Than Humans
Dogs have significantly more cannabinoid receptors in their brains than humans do, which means THC hits them harder, milligram for milligram. A dose that would barely register for a person can produce a dramatic neurological response in a dog. Their smaller body size compounds this: a single edible gummy designed for a human might represent a massive relative dose for a 20-pound dog.
Dogs are also more likely to eat the entire thing. They don’t nibble a corner of a brownie. They eat the whole pan, the wrapper, and sometimes the bag it came in. This means they’re often exposed to much higher doses than their owners realize, plus whatever chocolate, butter, or sweeteners came along for the ride.