About natural supplements · Feb 15, 2019
Please be careful with CBD products for dogs and cats
Dogs and cats handle cannabinoids in ways that are completely different from us, yet most products on the shelf are formulated and dosed as if that doesn’t matter.
CBD can help dogs and cats, but it’s not a straightforward “give them what works for humans” situation, and cutting corners is genuinely risky. Cats absorb CBD far less efficiently than dogs, ending up with roughly seven times less in their system at the same dose, and they can react badly in ways dogs simply don’t. On top of that, no cannabis product has been properly approved for veterinary use, label accuracy across the market is poor, and two dogs given exactly the same dose can end up with wildly different amounts in their bloodstream.
You can dose your dog or cat with CBD the same way you’d dose a human
I get why people think this. CBD is CBD, the endocannabinoid system exists across mammals, and the internet is full of weight-based conversion charts that lift numbers straight from human studies. It feels logical. It just isn’t.
Here’s the thing, different animals process CBD very differently, and even animals of the same species can vary wildly. One controlled study gave identical 2 mg/kg doses to both dogs and cats. The dogs reached serum CBD levels of 301 ng/mL, while the cats only managed 43 ng/mL. Cats absorbed far less of it, and on top of that, they showed some unpleasant reactions, excessive licking and head-shaking, that the dogs didn’t experience at all [1]. Same dose, very different story.
Dogs have their own quirks too. They have a much higher concentration of cannabinoid receptors (CB1) in parts of the brain that control movement and coordination, compared to humans [2]. That’s why THC causes that distinctive wobbly, frozen stance in dogs, something you simply don’t see in people. Any dosing model built on human data ignores that entirely.
And even within a single species, individual variation is huge. In one study, dogs receiving the exact same high dose had blood CBD levels ranging from 62.3 to 896.0 ng/mL, that’s a fourteen-fold difference between individual dogs [5]. You genuinely cannot predict where your dog will fall on that scale.
Add THC into the mix and it gets more complicated still. CBD slows down the liver enzymes that clear THC from the body, which means THC’s effects can be stronger and last longer when both are present [4]. Many whole-plant products contain both cannabinoids, so you’re not just juggling one variable, you’re juggling two that interact with each other.
Human dosing charts are simply the wrong starting point when you’re treating an animal. Anyone telling you otherwise is working well beyond what the evidence actually supports.
How cannabis works in dogs and cats: Receptors, metabolism, and why species differences matter
Cannabis sativa contains over 550 active compounds. The two most talked-about are cannabidiol (CBD) and tetrahydrocannabinol (THC), but whole-plant extracts also carry meaningful amounts of their raw, unprocessed forms, CBDA and THCA, which in oil-based products can actually be present at two to three times the level of CBD and THC themselves.
Dogs are not small humans, and their brains prove it
Dogs have far more cannabinoid CB1 receptors packed into their cerebellum, brainstem, and medulla than humans do. That difference in wiring is why THC causes a strange wobbly-standing response in dogs, known as *static ataxia*, that you simply don’t see in people. It’s also exactly why you can’t just borrow a dose from a human study and apply it to your dog. The brain is built differently, and it responds differently.
CBD slows down how the body handles THC
Here’s something that often gets overlooked: CBD puts the brakes on a group of liver enzymes called cytochrome P450 enzymes, the ones responsible for breaking down THC. When both cannabinoids are present together (as they are in most whole-plant extracts), CBD essentially slows THC’s exit from the body. The more CBD present, the more pronounced this effect. In a dog, where you’re already trying to keep THC exposure as low as possible, this interaction really does matter.
THC hangs around in dogs for a long time
CBD clears a dog’s system in around four hours. THC takes roughly 30 hours. Dogs also process THC in a way that’s quite different from humans, via a recycling loop through the liver and gut called enterohepatic recirculation, producing breakdown products that we don’t see in human metabolism. Add that to a brain loaded with cannabinoid receptors in sensitive areas, and THC build-up becomes a real concern rather than a theoretical one.
Cats and dogs are not interchangeable either
Under identical dosing conditions, cats ended up with CBD blood levels of 43 ng/mL, roughly seven times lower than the 301 ng/mL seen in dogs. Their overall exposure was similarly reduced. Cats also showed behavioural side effects during oil dosing that dogs didn’t. We don’t yet fully understand why the gap is so large, but it is large, and that makes cat-specific dosing non-negotiable.
Two dogs, same dose, wildly different results
Even among dogs, CBD blood levels at the same high dose ranged from 62.3 to 896.0 ng/mL, that’s more than a 14-fold difference between individual animals. Differences in how well each dog absorbs and processes CBD are the most likely explanation. It also means you can’t assume one dog’s response will look anything like another’s.
The oil your CBD is carried in is not a footnote
CBD delivered in oil is absorbed around four times better than CBD in powder form. And within oil-based products, something as seemingly minor as droplet size can drive up to a 455% difference in peak blood concentration. The carrier isn’t just packaging, it’s part of how much CBD actually reaches your dog’s system.
Whole-plant versus isolated CBD: the honest picture
There’s a genuine argument that whole-plant extracts, carrying a full range of minor cannabinoids, terpenes, and flavonoids alongside CBD, work better than isolated CBD on its own. This is often called the entourage effect. Some lab-based research suggests terpenes don’t directly activate cannabinoid receptors, but minor cannabinoids like CBDA and THCA may contribute through other routes entirely. The science here is still being worked out, I won’t pretend otherwise, but the signal is interesting enough to take seriously.
How to use CBD and hemp extracts in dogs and cats: what the evidence actually supports
Dosing: follow the research, not the label
– The most rigorous trial we have in epileptic dogs used 9 mg/kg/day oral CBD and found a real reduction in seizure days compared to placebo. That’s reassuring, but the same study flagged liver enzyme changes, plus more appetite loss and vomiting in the CBD group than the placebo group. So yes, there’s a benefit signal, and yes, there’s a side-effect signal. Both matter.
– Here’s the thing about CBD in dogs: two dogs given exactly the same dose can end up with wildly different amounts in their bloodstream, in one study, plasma levels at the same high dose ranged from 62.3 to 896.0 ng/mL. That’s not a rounding error, that’s a roughly fourteen-fold difference. “Start low and keep a close eye on things” isn’t just something people say, the science genuinely backs it up.
Formulation: oil beats powder, by a long way
The form your CBD comes in matters enormously, far more than most labels will tell you. An oil-based product delivers around four times more CBD into the bloodstream than the same amount in powder form. Sesame oil specifically pushed that up to eight times more than powder in controlled studies. And within oil-based products, something as technical-sounding as droplet size can shift peak blood levels by up to 455%. What that means in plain terms: if you’re using a powder or capsule, your dog is very likely getting a fraction of what you think you’re giving.
I always recommend oil-based whole-plant hemp extracts over isolated CBD powders, and this is a big part of why. There’s also a good botanical reason: in whole-plant extracts, the acid forms of the cannabinoids, CBDA and THCA, are present at two to three times the concentration of the more familiar decarboxylated forms, and early evidence suggests they may be pulling their own weight therapeutically.
Cats: a completely different animal, not just a smaller dog
I really can’t stress this enough. In a head-to-head pharmacokinetic study at the same dose, cats ended up with serum CBD levels of 43 ng/mL while dogs hit 301 ng/mL, cats were absorbing less than a seventh of what dogs did. On top of that, cats showed behavioural signs during oil administration, excessive licking and head-shaking, that simply didn’t appear in dogs. You cannot take a canine dose and apply it to a cat. The differences are too large, and the research doesn’t support it.
CBD and other medications: something worth knowing
CBD blocks a group of liver enzymes called cytochrome P450s, these are the same enzymes that process a huge range of medications. When CBD is given alongside THC, it slows THC clearance and amplifies its effects. More relevantly for most pet owners: if your dog is already on medication that the liver processes, phenobarbitone for epilepsy is a common one, adding CBD could alter how much of that drug is actually active in the body. This isn’t hypothetical; it’s a documented interaction. Please talk to your vet before introducing CBD alongside any existing medication.
THC: this isn’t a dosing question, it’s a safety question
Dogs have far more cannabinoid receptors (CB1) in the parts of the brain that control movement and basic body functions than humans do. That’s why THC causes a distinctive wobbly-stance syndrome in dogs, ‘static ataxia’, that you simply don’t see in people. THC also lingers in dogs: its half-life is around 30 hours, compared to just 4 hours for CBD, and it recirculates through the liver and gut, building up over time. There is no safe incidental THC dose for dogs. Any product with meaningful THC content should be off the table unless a vet is actively supervising.
What to keep an eye on
Going by the clinical trial data, the things worth monitoring are: liver enzyme levels (a straightforward blood panel from your vet), reduced appetite, and vomiting, especially at higher doses or when you’re first introducing the product. In cats, watch specifically for the behavioural signs that showed up in the pharmacokinetic research: excessive licking and head-shaking around the time of dosing.
What we’d recommend
Whole-plant hemp calming support for dogs and cats, formulated to actually reach the bloodstream.
See the product
Frequently asked questions
Can I give my cat the same CBD oil and dose I use for my dog?
No, and this is worth taking seriously. Cats absorb CBD far less efficiently than dogs. In one study, the same dose given to both species resulted in dogs reaching blood CBD levels of 301 ng/mL, while cats only got to 43 ng/mL. On top of that, cats showed some uncomfortable reactions during the oil itself, excessive licking and head-shaking, which dogs didn’t experience at all. What works for your dog simply isn’t a safe starting point for your cat.
Why is THC dangerous for dogs even at low doses?
Dogs have far more cannabinoid receptors (the CB1 type) packed into key parts of their brain, the cerebellum, brainstem, and medulla, than humans do. This is why THC causes a wobbly, frozen-looking reaction in dogs called ‘static ataxia’ that you simply don’t see in other species. To make things worse, THC hangs around in a dog’s system for roughly 30 hours, compared to just 4 hours for CBD. So any toxic effects last a long time. Human dosing guides are no use here at all.
Does CBD actually reduce seizures in dogs?
There is real evidence that it can help. A properly blinded study of 51 dogs with hard-to-treat epilepsy found that CBD at 9 mg/kg per day led to a 24.1% drop in seizure days, while the placebo group actually saw a 5.8% increase. That’s a meaningful result. But, and this matters, the same study found elevated liver enzyme levels and more cases of appetite loss and vomiting in dogs on CBD. So yes, there’s promise here, but it’s not without trade-offs that need watching.
How much does the formulation of a CBD oil actually matter?
Enormously, far more than most people realise. Research in human volunteers found that an oil-based CBD product delivered roughly four times the absorption of the same CBD in powder form. Sesame oil as the carrier pushed that up to eight times. And just tweaking the droplet size within an oil product produced a 455% difference in how much CBD actually reached the bloodstream. Two products with the same amount of CBD on the label can behave very differently inside the body.
Is whole-plant hemp extract better than isolated CBD for pets?
I think the whole-plant approach deserves more credit than it often gets. In dog studies, the lesser-known acid forms of cannabinoids, CBDA and THCA, showed up at two to three times the levels of regular CBD and THC in whole-plant extracts. THCA, in particular, has been reported to reduce seizures in children at doses ten to a hundred times lower than standard CBD doses. The ‘entourage effect’ is still debated, some lab work suggests terpenes don’t directly act on cannabinoid receptors, but the minor cannabinoid picture alone is reason enough not to dismiss whole-plant complexity.
How do I know the CBD product I’m buying contains what the label says?
Honestly, with a lot of products out there, you can’t be certain. No cannabis extract products have been formally approved for veterinary use in North America, and the gap in quality between licensed and unlicensed producers is significant, in both cannabinoid content and label accuracy. Add to that the fact that one study found dogs given the same dose had blood CBD levels ranging anywhere from 62 to 896 ng/mL, and you start to see why product quality isn’t just a nice-to-have. It’s the whole foundation.
Sources
- Single-Dose Pharmacokinetics and Preliminary Safety Assessment with Use of CBD-Rich Hemp Nutraceutical in Healthy Dogs and Cats
- The Endocannabinoid System of Animals – PMC
- The efficacy and safety of cannabidiol as adjunct treatment for drug-resistant idiopathic epilepsy in 51 dogs: A double-blinded crossover study
- Preliminary Investigation of the Safety of Escalating Cannabinoid Doses in Healthy Dogs
- Preliminary Investigation of the Safety of Escalating Cannabinoid Doses in Healthy Dogs
- Pharmacokinetic and Safety Evaluation of Various Oral Doses of a Novel 1:20 THC:CBD Cannabis Herbal Extract in Dogs
- Effect of two oral formulations of cannabidiol on responses to emotional stimuli in healthy human volunteers: pharmaceutical vehicle matters
- Minor Cannabinoids: Biosynthesis, Molecular Pharmacology and Potential Therapeutic Uses
- Minor Cannabinoids: Biosynthesis, Molecular Pharmacology and Potential Therapeutic Uses
- Pharmacokinetics of Cannabidiol, Cannabidiolic Acid, Δ9-Tetrahydrocannabinol, Tetrahydrocannabinolic Acid and Related Metabolites in Canine Serum After Dosing With Three Oral Forms of Hemp Extract
- Detecting and quantifying marijuana metabolites in serum and urine of 19 dogs affected by marijuana toxicity
- Cannabis sativa L. as a Natural Drug Meeting the Criteria of a Multitarget Approach to Treatment