Dog joint supplements: are they worth what you are spending?

Why is there no single answer to this?

Because “joint supplement” is a shelf, not a substance. Three very different things sit on it, they have been tested separately, and the results are not the same. One verdict for all of them would be wrong.

Here is the starting point. Many of the joint supplements on the market do not have solid evidence behind them, and none of them should be used in place of proper treatment. Two words there are worth holding on to. Many, not all. And the problem is substitution, not harm.

What does the evidence say about glucosamine and chondroitin?

This is the pair most Australian owners are buying, and it is the pair with the least encouraging news. If it is what you have been buying, you have a great deal of company and nothing to feel silly about.

Glucosamine and chondroitin have been tested hard, across dozens of controlled trials in dogs and cats. The result is a very marked non-effect. They should no longer be recommended for managing arthritis pain.

There is one thing that does not mean, and we would rather be clear about it. Those trials measured pain, and they did not test whether glucosamine does anything to cartilage over years. What it means in practice is simple: if you are giving glucosamine to make your dog more comfortable, we would not count on it doing that job.

Is green-lipped mussel different?

Yes, and it is worth separating out, because green-lipped mussel is not a glucosamine product. It is a source of omega-3, and that puts it in different company.

When these products are grouped for testing, green-lipped mussel sits with the omega-3 products rather than with glucosamine, and that is the group that came out well.

Here is the caveat. Those results were reported by group, not product by product. So green-lipped mussel sits in good company. That is not the same as saying it has been proven on its own.

It does have older evidence of its own. Two of the best-designed trials in this field looked at green-lipped mussel, and it came out with a moderate level of confidence behind it. Some prescription anti-inflammatories sit at that same level, and so does one particular glucosamine combination, which cuts against what we said a moment ago. We would rather show you the whole picture than half of it.

What about omega-3 and fish oil?

This is the one class where the evidence holds up, and it has held up twice, ten years apart.

Of all the joint supplements tested in dogs, omega-3 is the only one where the evidence is strong, and it has come out that way twice, a decade apart. Omega-3 products genuinely ease the pain of arthritis in dogs and cats.

There is also good evidence for what that looks like in a real consulting room. Across 131 arthritic dogs at 33 ordinary veterinary practices, dogs fed a fish-oil omega-3 diet needed less anti-inflammatory over twelve weeks. Worth knowing: that particular trial was funded by a pet food maker.

It is worth seeing what that describes: omega-3 alongside proper pain relief, letting the vet dial the medication down, rather than omega-3 instead of it.

What is worth spending the money on instead?

This is what we would talk you through if you rang and asked, and none of it is a product.

1. A diagnosis. “Arthritis” is a conclusion, not a starting point. A limp on a back leg can be a torn cruciate, a slipping kneecap, a hip problem or arthritis, and they are managed very differently.
2. Weight, if there is weight to lose. Dogs limp noticeably less once they have lost about 6% of their body weight. For a 30kg dog that is under two kilos. It costs nothing, and the evidence behind it beats the evidence behind most of the cupboard.
3. Actual pain relief. Arthritis is painful, the longer the pain goes untreated the worse it gets, and getting a sore dog comfortable again is the part we most want to help with. The options run from anti-inflammatories, to medicines for long-term pain, to treatments that slow cartilage breakdown. All of them are prescribing decisions we make with you, for your dog.
4. Changing the house, not just the dog. Shorter walks on even ground, skipping stairs, covering slippery floors, and a ramp for the car. Slippery floorboards undo a lot of good treatment.
5. Omega-3, discussed with us. If you are going to buy one thing, this is the class with the evidence behind it. We can talk you through the form and the amount rather than leaving you to guess, because that part is a prescribing decision too.

If your dog has started running with both back legs together, our page on bunny hopping explains why we would look at the hips and knees, and hydrotherapy for dogs covers where water-based exercise fits once we know what is wrong.

When should you stop trying supplements and ring us?

Trying a supplement is a slow, low-stakes experiment, and for a mildly stiff older dog there is no harm in it at all. Some situations are neither slow nor low-stakes, though, and another month of tubs costs your dog time. Arthritis is painful, and the longer the pain goes untreated, the worse it gets.

We would much rather you rang us than bought anything else, if you notice any of these:

• Your dog will not put the leg down at all, or is holding it up.
• The limp came on suddenly, or straight after a yelp, a fall or a run.
• A joint is swollen, hot, or your dog objects to it being touched.
• It is getting worse rather than better over a couple of weeks.
• Your dog is struggling to get up, is reluctant on stairs, or has stopped doing something it used to enjoy.
• It is a young dog. Limping in a dog that is still growing is a different set of problems from arthritis, and worth looking at early.
• You have been giving a supplement for a month or more and the dog is still sore. That is your answer, and it is worth acting on rather than changing brands. There is nothing wrong with having given it a try.

What happens when we examine that leg?

We watch your dog walk, then gently feel every joint in the leg and compare it with the other side. A great deal is settled at that point, and no supplement can do that for you. What we recommend afterwards is built around your dog and we adjust it as they go, so you are never left guessing on your own.

• Imaging where it changes the answer. X-ray and ultrasound are on site here. CT scans are done at our sister practice, Advanced Vet Care in Lane Cove, and we refer your pet there when one is needed.
• A plan you can actually follow, covering pain relief, weight, exercise and what to change at home, and we are here to help with any of it.
• A straight answer on supplements, including telling you to stop buying one if we do not think it is earning its place.
• Orthopaedic surgery here if it turns out to be needed, so a diagnosis does not automatically become a referral somewhere else.

The Macquarie Veterinary Hospital team

Macquarie Park

We do orthopaedic surgery here at Macquarie Park, and we see emergencies during our opening hours. Medically reviewed by Dr Michael Stephen, BVSc, MVSc.