Cat Safety

How cats differ from dogs in absorbing and metabolising cannabinoids, and what the published feline safety research actually found.

Healthy relaxed ginger cat resting on a sunlit windowsill in warm natural daylight

Cat Safety: What the Research Actually Says About Hemp and Cats

Cats are not small dogs, and on this subject the difference is measurable rather than theoretical. They absorb cannabinoids differently, they metabolise them by a different route, and the tolerability picture is genuinely its own thing.

You will still find widely-read pages claiming no feline research exists. That has not been true since 2019, and this page walks through what has actually been published.

Why Cats Are Different: The Glucuronidation Story

Cats carry an inactivated version of the UGT1A6 gene — a pseudogene shared across the whole cat family, disabled by mutations fixed millions of years ago during their evolution as obligate carnivores. It leaves them poor at glucuronidation, the process used to clear phenolic compounds. It is why paracetamol and aspirin are so dangerous to cats.

It is often stated online that this means cats "can't process CBD". That overstates it. The feline pharmacokinetic data show markedly lower plasma exposure than dogs, and a 2025 review notes cats favour a different phase-one hydroxylation route, forming 6-hydroxylated metabolites rather than the 7-OH-CBD dogs and humans produce. The honest phrasing is that cats handle these compounds differently — not that they cannot handle them at all.

Cats Absorb Far Less Than Dogs

The clearest single finding. In a study giving the same 2 mg/kg twice daily to both species, dogs reached a peak plasma concentration of about 301 ng/mL and cats about 43 ng/mL — roughly a seventh, on an identical amount per kilogram. The paper is open access.

This is why a cat product should be formulated and portioned for cats rather than measured out of a dog bottle, and why comparing milligram figures across species tells you very little.

Food Matters Even More in Cats

A feline study comparing fed against fasted administration found roughly an elevenfold increase in relative oral bioavailability when given with food, along with a later peak — about 4.7 hours fed. Read it in Frontiers in Veterinary Science.

Give it with a meal. In cats this is not a marginal optimisation.

Long-Term Tolerability

The strongest safety dataset is a randomised, blinded, placebo-controlled study feeding healthy cats about 4 mg/kg daily with meals. Over a four-week arm, ALT ran about 1.44 times placebo. Over the 26-week arm, ALT was statistically equivalent to placebo at every timepoint, with unremarkable AST, ALP, bilirubin and bile acids. It is published here.

A separate dose-escalation study took healthy cats far above normal amounts and reported adverse events that were mild, transient and self-resolving, with no clinically significant bloodwork changes. Notably, the lethargy and unsteadiness appeared in arms containing THC, not in CBD-only arms.

Balanced against that: in a real-world field study of cats with joint discomfort, 46% discontinued, and well over half of those did so because of vomiting or diarrhoea. Both halves of that picture belong on the same page.

The Thing Cats Actually Object To

In the twelve-week study, the most common observations in cats were excessive licking in about 35% of observation periods and head-shaking in about 25% — during administration. The authors attributed this to palatability rather than any systemic effect.

Which is a useful, unglamorous finding: with cats, the practical obstacle is usually taste and delivery, not pharmacology. Mixing into food is both better absorbed and better tolerated.

Essential Oils Are a Separate Question — Do Not Conflate Them

Concentrated essential oils are genuinely dangerous to cats. Tea tree, pennyroyal, wintergreen, citrus, cinnamon, peppermint and pine are all documented hazards, and the same reduced enzyme capacity is part of why.

That is not the same exposure as trace terpenes in a diluted hemp extract. Essential oils are near-neat preparations, often applied to skin or diffused; the terpene content of a hemp extract in a food-grade carrier is orders of magnitude lower. Different mechanism, different exposure.

That distinction does not by itself make hemp extract safe for cats — the feline tolerability data above does that work, and it comes with real caveats. Never give a cat an essential oil.

What This Means Practically

Use a product formulated and portioned for cats. Give it with food. Start at the low end and build slowly. Tell your veterinarian, especially if your cat has any liver history or takes other medication. Watch for vomiting or reduced appetite in the first fortnight — that is when the field data says people stop.

Browse CBD Hemp for Cats, and see serving size for the general framework.

Frequently Asked Questions

Is hemp safe for cats? Healthy cats tolerated about 4 mg/kg daily for 26 weeks in a controlled trial with liver values equivalent to placebo. In a real-world study of cats with joint discomfort, though, nearly half discontinued, mostly for digestive upset. Both findings are real; discuss it with your vet.

Can cats have CBD oil? Cats have been given it in published research, and the tolerability data are reasonably encouraging in healthy animals. Use a cat-specific product and involve your veterinarian.

Why do cats process it differently from dogs? Cats lack a functioning UGT1A6 enzyme and clear phenolic compounds poorly, and they favour a different metabolic route. The measurable result is far lower plasma concentrations than dogs at the same amount.

Do cats really absorb less? Yes — about 43 ng/mL peak against 301 ng/mL in dogs on the same 2 mg/kg.

Does it raise liver enzymes in cats? A short four-week study saw ALT around 1.44 times placebo; the 26-week study found ALT equivalent to placebo throughout. One cat in an earlier study had a persistent ALT elevation. Ask your vet about bloodwork if your cat has any liver history.

Does giving it with food matter? More than in dogs — roughly elevenfold higher bioavailability when fed.

Is hemp extract toxic to cats like essential oils are? No, and the two should not be equated. Essential oils are concentrated, near-neat preparations; hemp extract carries trace terpenes in a food-grade carrier at vastly lower exposure.

Why does my cat lick and shake her head afterwards? Most likely taste. Excessive licking and head-shaking were the most frequently recorded observations in the feline study and were attributed to palatability. Mix it into food.

Are there actually studies in cats? Yes — feline pharmacokinetic and safety work has been published from 2019 onward, including a 26-week controlled tolerability study. Pages claiming none exists are out of date.

Is THC dangerous to cats? Yes. Sedation-type effects in the escalation study clustered in the THC-containing arms. See THC.

Further reading: the ASPCA Animal Poison Control Center on CBD in pets.