Quick answer: for a dog with arthritis, the supplement with the strongest evidence is omega-3 (EPA and DHA from fish oil, or green-lipped mussel). A 2022 review of 72 trials found a clear effect on arthritis pain for omega-3, while glucosamine and chondroitin did not relieve pain. Any supplement goes alongside your vet's treatment, never instead of it. If you want one daily joint product to sit alongside that plan, we'd recommend MedPaw Hip & Joint Chews: green-lipped mussel plus five other key joint actives in a soft chew.
Transparency note: this page is written by MedPaw, which makes a joint supplement. We've graded the evidence honestly, including where it doesn't favour ingredients we use. Checked 9 October 2026.
What arthritis does to a dog
Arthritis in dogs is almost always osteoarthritis: the cartilage that cushions a joint wears and the joint becomes inflamed, stiff and sore. It's common. A Royal Veterinary College study found it recorded in around 2.5% of UK dogs each year, and dogs at or above their breed's average weight had 2.3 times the odds of a diagnosis (Anderson et al., 2018). It can't be cured, but pain can be managed well, and that's where treatment starts. Our guide to arthritis symptoms, causes and management covers the condition itself.
Treatment comes first
Supplements are complementary feeds. They are not painkillers and they don't treat arthritis. The things that make the biggest difference are:
- Pain relief from your vet, such as an anti-inflammatory (see our NSAIDs guide) or the monthly injection Librela.
- Weight loss if your dog is carrying extra. In obese dogs with arthritis, lameness improved after losing just over 6% of body weight (Marshall et al., 2010).
- Steady, controlled exercise, plus physiotherapy or hydrotherapy.
- A safer home: rugs on slippery floors, a ramp, a supportive bed.
Go back to your vet promptly if:
- your dog stops putting weight on a leg, or the limp gets worse
- they cry out, won't settle at night or stop wanting to walk
- a joint becomes hot or swollen
- they vomit, have diarrhoea or black stools, or go off their food while on pain relief
- they seem low or withdrawn (pain often shows as a change in mood)
Arthritis supplements, graded by evidence
Most of these grades come from the largest review to date: 72 trials of joint supplements in dogs and cats (Barbeau-Grégoire et al., 2022).
Supplements for dogs with arthritis: what the research shows
| Supplement | What the research shows | Our grade |
|---|---|---|
| Omega-3 (fish oil, omega-3 enriched diets) | Clear effect on arthritis pain across most trials; a large multicentre study also found benefits in dogs fed an omega-3 enriched food (Roush et al., 2010) | Strongest |
| Green-lipped mussel | Improved pain and mobility against placebo, though less than the anti-inflammatory carprofen (Hielm-Björkman et al., 2009) | Good |
| Cannabidiol (CBD) | Most small trials positive; needs more research. Talk to your vet (see our CBD guide) | Promising |
| Collagen, including UC-II | Some positive results, but from small, low-quality trials | Weak |
| Turmeric (curcumin) | Trials conflict, some positive and some negative | Mixed |
| Boswellia, devil's claw | Only tested as part of combination products, so their own effect is unclear | Unproven alone |
| Vitamin E | A 2023 placebo-controlled trial of 57 dogs with arthritis found no improvement in pain or lameness (JVIM, 2023) | Not shown |
| Glucosamine and chondroitin | Did not relieve pain in the 2022 review; still widely used to support cartilage | Not shown for pain |
Two practical points. First, the omega-3 evidence is for proper doses of EPA and DHA, which usually means a fish oil or a therapeutic diet your vet recommends; see our best fish oil for dogs' joints guide. Second, "not shown to relieve pain" doesn't mean useless: glucosamine and chondroitin are given to support cartilage, and many owners use them alongside pain relief. Just don't expect them to work like a painkiller.
Using a supplement alongside treatment
- Tell your vet what you're giving, and take the tub along. See telling your vet about supplements and joint supplements and medication.
- Change one thing at a time, so you can tell what helped.
- Keep a weekly diary of getting up, stairs and walks, or use a pain score chart.
- Give it six to eight weeks before judging.
- Swap rather than stack joint supplements: one good product beats three overlapping ones.
Just had the diagnosis? Our guide to choosing a joint supplement after an arthritis diagnosis walks through the first weeks.
How MedPaw fits
MedPaw Hip & Joint Chews: main amounts per chew, and the evidence behind each
| Active | Per chew | Evidence for arthritis |
|---|---|---|
| Green-lipped mussel | 70mg | Good |
| Glucosamine | 170mg | Cartilage support; not shown for pain |
| Chondroitin | 70mg | Cartilage support; not shown for pain |
| MSM | 185mg | Limited |
| Boswellia serrata | 30mg | Unproven alone |
| Hyaluronic acid | Amount not published | Limited |
MedPaw is a broad joint chew, not a high-dose fish oil, and we don't claim its amounts match those used in any particular trial. If your vet recommends omega-3 at an arthritis dose, you can give that alongside it.
Our recommendation: keep your vet's treatment as the foundation, then add MedPaw as your dog's daily joint support. It's a soft chicken and bacon chew most dogs take like a treat, so it's easy to keep going every day. Give it six to eight weeks, and if you're not happy, email us within 60 days and we'll refund you, with nothing to send back. MedPaw is a complementary feed, not a medicine. It contains green-lipped mussel (mollusc) and brewer's yeast (gluten), so it isn't suitable for dogs with a shellfish allergy, and please check with your vet before starting it if your dog has another condition or takes medication. Try MedPaw Hip & Joint Chews.
Comparing brands? See our best joint supplements for dogs in the UK, or for older dogs, best joint supplements for senior dogs.
What is the best supplement for a dog with arthritis?
Omega-3 has the strongest evidence for easing arthritis pain, followed by green-lipped mussel. For an all-round daily joint chew to use alongside your vet's treatment, we'd recommend MedPaw Hip & Joint Chews, which contains green-lipped mussel plus glucosamine, chondroitin, MSM, hyaluronic acid and Boswellia.
Do arthritis supplements for dogs actually work?
Some do more than others. In a 2022 review of 72 trials, omega-3 products clearly reduced arthritis pain, while glucosamine and chondroitin did not. Supplements help some dogs, not all, and they work gradually alongside treatment rather than replacing it.
Can a supplement replace my dog's arthritis medication?
No. Don't stop or reduce prescribed pain relief without talking to your vet. Green-lipped mussel, one of the better-evidenced supplements, was less effective than a prescription anti-inflammatory in a head-to-head trial.
Should I give fish oil or a joint chew to my arthritic dog?
They do different jobs, and many dogs have both. Fish oil provides omega-3 at the levels used in arthritis studies; a joint chew provides cartilage and joint-support actives. Ask your vet about the right fish oil dose for your dog.
Is turmeric good for dogs with arthritis?
The evidence is mixed: some trials found a benefit and others didn't. Curcumin is also poorly absorbed. If you want to try it, ask your vet first, especially if your dog takes other medicines.
How long before an arthritis supplement makes a difference?
Allow six to eight weeks of daily use, and up to three months for some dogs. Keep a weekly diary so you can compare fairly, and see your vet sooner if your dog gets worse.
