Most dogs recover from THC intoxication within 12 to 36 hours, though mild symptoms can occasionally linger up to 72 hours depending on the dose and how the dog was exposed. If your dog got into your edibles, flower, or a discarded joint on a walk, the “high” is almost certainly temporary, but it can look alarming while it lasts.
What Your Dog Looks Like Right Now
The most common signs, based on thousands of cases logged by the Pet Poison Helpline between 2018 and 2023, are lethargy (about 30% of cases), loss of coordination (21%), and vomiting (15%). Your dog may stumble like they’re drunk, stare blankly into space, or seem unable to stand. Urinary incontinence is also common, so don’t be surprised if your house-trained dog starts dribbling urine.
Other things you might notice: dilated or glassy eyes, drooling, head bobbing, trembling, and an exaggerated startle response to sounds or touch. Some dogs become agitated instead of sedated, pacing or vocalizing. Changes in heart rate, either unusually slow or fast, can also happen. Dogs have far more cannabinoid receptors in their cerebellum and brainstem than humans do, which is why the loss of coordination and sedation can look so much more dramatic than what you’d expect from a human getting high.
Why It Lasts So Long in Dogs
THC is fat-soluble, meaning it gets stored in your dog’s body fat and released slowly over time. Pharmacokinetic research on dogs found a terminal half-life of roughly 8 days for THC in plasma, which sounds terrifying but doesn’t mean your dog will act impaired for a week. The visible symptoms resolve much sooner because they depend on the concentration of THC actively hitting the brain, not the trace amounts slowly clearing from fat tissue.
Your dog’s liver processes THC into multiple metabolites in sequence, and about 10 to 15 percent of those metabolites recirculate through the gut before being eliminated. This recycling loop is one reason the effects can feel like they drag on longer than you’d expect. The practical result: a dog that ate a small amount of flower may seem normal in 12 hours, while a dog that got into a potent edible could be wobbly and out of it for a full day or more.
Edibles Hit Harder
The route of exposure matters a lot. Inhaling secondhand smoke produces a milder, shorter episode. Eating an edible delivers a much higher dose that absorbs slowly through the gut, extending both the peak and the tail of symptoms. Dogs can show mild clinical signs at THC doses as low as 0.3 to 0.5 mg per kilogram of body weight, and moderate signs above 2 to 3 mg/kg. A single commercial edible gummy can easily exceed that threshold for a small dog.
Edibles also carry a second risk that pure cannabis doesn’t: the other ingredients. Chocolate edibles add chocolate toxicity on top of the THC. Anything sweetened with xylitol (sometimes listed as birch sugar) is genuinely dangerous, since xylitol can cause life-threatening drops in blood sugar and liver failure in dogs. If your dog ate a cannabis-infused chocolate bar or sugar-free candy, the THC may actually be the least of your concerns.
What You Can Do at Home
For a mild case where your dog is just sleepy and a bit uncoordinated, the main job is keeping them safe and comfortable while they ride it out. Put them in a quiet, dimly lit room away from stairs, since their coordination is compromised and a fall could cause injury. Their heightened sensitivity to sound and touch means a calm environment genuinely helps. Keep fresh water nearby, but don’t force them to drink. Place towels or puppy pads underneath them in case of urinary dribbling.
Check on them every 30 minutes or so. You’re watching for two things: that they remain rousable (you can wake them up, even if they immediately go back to sleep) and that symptoms are stable or improving rather than getting worse.
Signs That Need a Vet
Most THC exposures in dogs are not fatal. The minimum lethal oral dose is above 3 grams of pure THC per kilogram of body weight, a quantity that’s virtually impossible to reach through accidental exposure to consumer products. But “not fatal” doesn’t mean “never needs medical attention.”
Get to a vet if your dog has seizures, becomes completely unresponsive or comatose, shows significant difficulty breathing, or can’t regulate their body temperature (feeling unusually hot or cold to the touch). Persistent, severe vomiting also warrants a visit, especially in a small dog that can dehydrate quickly. If you know or suspect the product contained chocolate or xylitol, that alone is reason enough to go.
Be honest with the vet about what your dog ate. They aren’t going to judge you or report you. They just need accurate information to treat your dog correctly, and it’s worth knowing that over-the-counter human urine drug tests are unreliable for detecting THC in dogs, so the vet may not be able to confirm the exposure through testing alone. Your account of what happened is the most useful diagnostic tool they have.
The Typical Recovery Arc
Here’s what most owners describe seeing. In the first one to three hours after ingestion, symptoms ramp up: the wobbling starts, the glazed expression sets in, and the dog either becomes very quiet or unusually anxious. Peak impairment usually hits somewhere between two and six hours in. After that, there’s a slow, gradual return to normal. Many dogs are noticeably better by 12 to 18 hours and essentially back to themselves by 24 to 36 hours, though they may sleep more than usual for another day.
If your dog inhaled secondhand smoke rather than eating something, the timeline is compressed. Onset is faster (minutes rather than an hour), peak is earlier, and most dogs bounce back within 6 to 12 hours.
Dogs that ate a large dose of a high-potency edible sit at the other end of the spectrum. These cases can take two to three days to fully resolve, with the dog cycling between sleep and brief, groggy periods of wakefulness before gradually coming around. As long as they’re rousable, drinking small amounts of water, and not showing the red-flag symptoms listed above, time is the primary treatment.