Disclosure: BDI.ie is run by the team behind Dr. Hemp Me and CBD Éire. Where we mention those brands, we have a commercial interest. More about who we are.
Last reviewed: October 2026
Pet shops and websites are full of joint supplements for dogs, from glucosamine chews to green-lipped mussel powder and CBD oils. Which have real evidence, which are worth trying, and how do they fit with your vet’s treatment? This guide compares the main options honestly.
Start with a diagnosis
Joint pain in dogs can come from osteoarthritis, dysplasia, ligament injuries, immune-related joint disease or even bone tumours in older large dogs. Supplements are not a substitute for finding out what is wrong. Ask your vet to examine your dog before spending money on supplements.
Supplements compared
| Option | Evidence in dogs | Notes |
|---|---|---|
| Omega-3 (EPA/DHA from fish oil) | Reasonable | Used in prescription joint diets; dose by weight; can cause loose stools |
| Prescription joint diets | Reasonable | Combine omega-3s with weight control; ask your vet |
| Green-lipped mussel | Mixed, some positive | Avoid in dogs with shellfish allergy |
| Glucosamine and chondroitin | Weak and mixed | Widely used; generally safe |
| Turmeric | Very limited | Poor absorption; can interact with some medicines |
| CBD | Limited and mixed | No authorised CBD vet medicine in Ireland; possible liver enzyme changes |
Omega-3 fatty acids
Omega-3 fatty acids from fish oil have the most consistent evidence among joint supplements for dogs, and are the basis of several veterinary joint diets. Your vet can recommend a dose based on your dog’s weight. Fish oil adds calories, so account for it in your dog’s food, and it can cause loose stools at high doses. Do not use cod liver oil as a joint supplement, as it can provide too much vitamin A and D.
Glucosamine and chondroitin
These are the most popular joint supplements, but studies in dogs are mixed. They are generally safe, so some owners try them for a couple of months and judge the effect with their vet.
CBD and joint pain in dogs
Some small studies in dogs with osteoarthritis reported better owner-rated mobility with CBD, while others did not. Studies are short and products vary, and some found raised liver enzymes. If you and your vet decide to try CBD, use a product made for pets with a lab report showing THC is not detected. See CBD oil for dogs in Ireland.
Avoid these
- Human supplements with xylitol or high vitamin doses.
- Human painkillers of any kind.
- Products promising to “cure” arthritis or “regrow cartilage”.
- Combining several supplements at once, which makes it impossible to tell what helps.
Weight: the biggest thing you can change
Extra weight puts more load on painful joints and is linked to shorter, less comfortable lives in dogs. Studies in Labradors found that dogs kept lean lived around two years longer and developed arthritis later. Ask your vet for your dog’s ideal weight and body condition score, measure food rather than guessing, count treats as part of the daily allowance, and swap some treats for pieces of carrot or green beans. Weigh your dog every few weeks at the vet clinic.
The right kind of exercise
Dogs with painful joints still need exercise, but the type matters. Several shorter, steady walks on grass or soft paths are better than one long walk or bursts of ball-chasing, which involve sudden stops and twists. Swimming and hydrotherapy are excellent low-impact options; some Irish vet practices and rehabilitation centres offer hydrotherapy. Avoid long runs alongside bikes and repeated jumping in and out of cars. On colder Irish days, a short warm-up walk before letting your dog run helps stiff joints loosen.
What the law in Ireland says about pet CBD
Pet CBD products can be sold in Ireland as general supplements if they contain no THC and make no medical claims. Anything claiming to treat joint pain in dogs would be a veterinary medicine, and veterinary medicines need authorisation from the Health Products Regulatory Authority (HPRA). There is currently no authorised CBD veterinary medicine in Ireland, so no CBD product can legally claim to treat joint pain in dogs.
If you and your vet decide to try CBD
- Talk to your vet first, especially if your dog takes any medicine; CBD can affect how some drugs are processed.
- Use a product made for pets, with dosing guidance by body weight.
- Check the lab report: batch number matching the bottle and THC not detected. THC is toxic to dogs.
- Start at the lowest suggested amount and keep it steady for a week or two.
- Watch for side effects such as drowsiness, loose stools, increased thirst or wobbliness, and stop if they occur.
- Keep the vet treatment plan going. CBD should never replace prescribed pain relief.
Safety reminders
- Never give dogs human gummies or sweets; xylitol, a sweetener in some products, is extremely toxic to dogs.
- Never give human painkillers unless your vet prescribes them.
- Store all CBD products where your dog cannot reach them.
- Cats process many substances differently from dogs; use only products made for cats and ask your vet.
Our position
BDI.ie is run by the team behind Dr. Hemp Me, which sells a THC-free pet CBD oil. We do not claim it treats joint pain in dogs. Your vet is the right person to diagnose and treat your dog, and any CBD routine should be agreed with them.
Keep a simple diary
Whatever you try for joint pain in dogs, note each day how far your dog walked, how easily they got up, their appetite, sleep and mood, and any medicines or supplements given. After a few weeks, review it with your vet. Small changes are much easier to spot on paper than from memory.
How to trial a supplement properly
- Agree with your vet which supplement to try and for how long, usually six to eight weeks.
- Keep everything else the same: food, exercise, other medicines.
- Score your dog weekly on getting up, walking, stairs and mood, and video them walking at the start and end.
- Review with your vet. If you see no clear difference, stop and save your money.
Reading pet supplement labels
Pet supplements are less tightly regulated than veterinary medicines. Look for the amount of each active ingredient per dose, clear dosing by weight, a batch number and expiry date, and a manufacturer you can contact. Be cautious about vague “proprietary blends” that do not state amounts. For CBD products, ask for a lab report for the batch.
Puppies and growing dogs
Joint health starts early. For large-breed puppies, feed a diet formulated for large-breed growth, avoid overfeeding, and avoid long runs and repetitive jumping until growth plates close. Ask your vet about screening for hip and elbow dysplasia if your breed is at risk. Prevention does more than any supplement later.
Cost
Supplements can cost more over a year than people expect. A prescription joint diet or omega-3 supplement with good evidence is often better value than several products with weak evidence. Your vet can help you prioritise.
Cats and joint pain
Cats get arthritis too, but hide it well. Signs include no longer jumping onto high surfaces, missing the litter tray, reduced grooming and sleeping more. Cats are very sensitive to many substances, including some essential oils and medicines that are safe for dogs, so never give a cat a dog supplement or human product. Ask your vet about licensed treatments for feline arthritis and cat-specific diets.
The simplest, best-evidenced steps for joint health are free or cheap: keep your dog lean, walk little and often on soft ground, and see your vet early when you notice stiffness.
Supplements, if used, are a small extra on top of those foundations, not a replacement for them.
Your vet is your best guide.
Frequently asked questions
What is the best joint supplement for dogs?
Omega-3 fatty acids from fish oil have the most consistent evidence. Ask your vet about dose and joint diets.
Does glucosamine work for dogs?
Evidence is weak and mixed, though it is generally safe.
Is CBD good for dog joint pain?
Evidence is limited and mixed. Talk to your vet before trying it.
Can I give my dog fish oil?
Usually yes at a vet-recommended dose. Avoid cod liver oil as a joint supplement.
Is green-lipped mussel safe for dogs?
Generally, but avoid it in dogs with shellfish allergies.
Should I give several supplements together?
Better to try one at a time so you can judge what helps.
Do joint diets work?
Prescription joint diets with omega-3s have reasonable evidence. Ask your vet.
When should I see a vet about joint pain?
Before starting supplements, and urgently if your dog cannot bear weight or is in obvious pain.
Related guides
This guide is for general information only and is not veterinary advice. Pet CBD products are not veterinary medicines. Always speak to your vet before giving your pet any supplement.