The Canine Ledger

CBD for Dogs: The Legal Position, and the Unknowns

In the UK, CBD for animals counts as a medicine, and Canada has authorised none. What the regulators say, and what four arthritis trials found.

Written by thecanineledger

If your dog has eaten a cannabis product meant for people, call your vet or an animal poison line now. Edibles can contain THC, the part of cannabis that causes a high, and other ingredients that are toxic to dogs.

Our note: This advice is ours.

→ Cannabis and Edibles

The UK’s veterinary medicines regulator says: “We consider that veterinary products containing Cannabidiol (CBD) are veterinary medicines and should be regulated as such.” (Veterinary Medicines Directorate, statement of 14 September 2018).

While CBD products for pets are easy to find online, that doesn’t make them legal or proven. This page sets out what regulators in the UK and Canada say, and what the trials in dogs with arthritis found. It doesn’t cover the US.

1. The UK

A medicine, not a supplement. CBD products for animals “now require a marketing authorisation before they can be sold or supplied in the UK.” A marketing authorisation is the licence a medicine needs.

None licensed in 2018. “There are currently no CBD based products that have been granted a UK veterinary marketing authorisation.”

What a vet can do. “a veterinary surgeon may prescribe a legally obtained human CBD product under the provisions of the prescribing cascade.” The cascade is the rule that lets vets use unlicensed medicines when no licensed one exists.

Giving it without a prescription. “Administration of an unauthorised product containing CBD without a veterinary prescription is an offence under Regulation 8 of the VMR.” VMR is the Veterinary Medicines Regulations.

Still current. The regulator’s list of substances it treats as medicines, updated on 25 September 2026, lists CBD as “Medicinal at any level” (Veterinary Medicines Directorate, Substances recognised as medicinal by function in veterinary medicines).

Our note: We didn’t check the UK product database, so a CBD product may have been licensed since 2018.

2. Canada

None authorised. Health Canada says: “Currently, there are no authorized veterinary drugs containing cannabis (including CBD).” (Health Canada, Towards a pathway for health products containing cannabidiol: Veterinary drugs containing cannabidiol for animal use).

Hemp products are separate. The page notes “There are notified VHPs in Canada containing hemp”. VHPs are veterinary health products, a lighter category that is notified, not authorised.

A possible change. Health Canada says it “is committed to exploring a regulatory pathway for veterinary drugs containing CBD (VDCC) that may be accessed without a prescription.” It hasn’t happened yet.

Our note: The Health Canada page shows it was last modified on 7 March 2025.

3. What a 2025 review of four trials found

An evidence summary. In 2025, a review in Veterinary Evidence, the journal of the UK organisation RCVS Knowledge, looked at four trials of CBD oil added to usual arthritis treatment (Yeung and Uquillas, Veterinary Evidence 2025). The next points report what the review says.

Owners and vets saw a difference. The review says “Three out of the four reviewed studies showed a significant effect of CBD oil in reducing pain and improving activity of dogs based on subjective pain and activity scoring systems by owners and veterinarians”.

Measurement didn’t. The review says the one trial that used objective gait analysis “displayed no significant improvement of locomotion”.

The verdict. The review’s rating: “Strength of evidence Weak.”

A liver enzyme. The review reports that in one trial, “9/16 dogs showed significant increase in alkaline phosphatase (ALP) over time from baseline by week 4 in the CBD oil treatment group”. ALP is a liver enzyme measured in blood tests.

What it doesn’t show. The trials were small and short, and used different products. The review doesn’t report who funded them, so we looked at each trial.

The four trials. We read three in full. For the fourth, we could read only the abstract.

Brioschi 2020, Italy. At a university hospital in Milan, 21 dogs were split at random into two groups for 12 weeks. Nine got CBD on top of their other pain treatment, and 12 got the other treatment alone. Owners’ pain scores were lower in the CBD group at 1, 2 and 4 weeks. There was no placebo oil, which the authors say “may have caused a placebo effect for the owners”. “This research received no external funding.” The authors declared no conflict of interest (Brioschi et al., Animals 2020).

Gamble 2018, US. At Cornell University, 16 of 22 dogs finished the trial. Each got CBD oil for 4 weeks and a dummy oil for 4 weeks, in random order. Neither owners nor vets knew which was which. Both reported less pain while the dogs were on CBD. A company that sells CBD products paid for the trial, through a grant to Cornell “to study this product”. The authors declared no conflict of interest (Gamble et al., Frontiers in Veterinary Science 2018).

Kogan 2020, US. In Colorado, 37 dogs with long-term pain, mostly from arthritis, started CBD oil, and 32 finished the 90 days. Every dog got CBD, and there was no comparison group. “Of the 32 dogs that completed the study, 30 dogs demonstrated improved pain support.” The authors call it “an open study with no placebo control group”, with “a potential for bias” because one vet assessed every dog. That vet is one of the authors and is based at a private pain clinic. The paper has no funding or conflict of interest statement, and doesn’t say where the oil came from (Kogan et al., AHVMA Journal 2020).

Mejia 2021, US. At Colorado State University, 23 dogs got CBD for 6 weeks and a placebo for 6 weeks, in random order, in a “double-blinded” trial. It measured gait and activity with equipment, and also used standard questionnaires. “There were no differences noted between groups at any time point for any of the recorded outcome measures.” Liver enzymes rose in 14 dogs on CBD, and 2 vomited (Mejia et al., Journal of the American Animal Hospital Association 2021).

Our note: For Mejia 2021 we could read only the abstract, which doesn’t say who funded the trial or whether the authors had conflicts. Of the other three, one had no outside funding, one was paid for by a company that sells CBD products, and one has no funding statement.

→ Fish Oil for Arthritis: What the Trials Show · → Arthritis Treatment: What Works, From Weight to Medication

4. What we could not verify

Commonly saidWhat we found
“CBD is a legal supplement for pets”Not in the UK. The regulator treats it as a medicine at any level.
“Vets can prescribe CBD”In the UK, yes, under the cascade, as of the 2018 statement. Canada not confirmed.
“CBD is proven for arthritis”Weak evidence, in a 2025 summary of four trials.
“Hemp products are the same as CBD medicines”No, in Canada. They’re a separate, notified category.
“The rules are the same in the US”Not checked.

Sources

Always confirm with your vet before acting on anything on this page.

This is not legal advice. It is our reading of the laws and rules as we best understand them from our research, and no lawyer has reviewed it. We state what the sources say and don't bend them to fit a story. Laws differ by place and change over time, so check the current rules where you live.