dogs and glucosamine

Penny takes a glucosamine product every day. Many people have commented that seeing she's only three, she shouldn't need to take it. However, our vet has suggested she stay on it so I've decided to take his word for it. The general opinion seems to be that even if it does no good, at least it won't harm her.

Because of this, I was interested to read that our local consumer society has reviewed the use of glucosamine for humans. An article in The Age newspaper gave a general overview of the review. It said that of the many glucosamine products studied, many did not have enough glucosamine in them to have an effect, and that there's little evidence that glucosamine has anything other than a placebo effect.

So, if a placebo effect only occurs because the person taking the product believes it will work, it shouldn't work for our dogs, then - after all, they don't know that the medications or alternative products we give them are intended to relieve joint pain. At least the article says that clinical trials show that this product is generally safe. However, on the radio today I heard a commentator say that we shouldn't assume that alternative medicines are always safe, because we have to remember that any product can interfere with the working of another medication. Luckily, Penny's not on anything else.

There is an online general overview of the study, by Choice, our consumer association magazine. A more detailed report is 'user pays', but I think it would be okay to report what I found by reading it.

Glucosamine is a natural product of the human body - I assume dogs' bodies would produce it also - and it helps with the formation and repair of cartilage. My dictionary defines cartilage as firm, whitish, flexible connective tissue found in the articulating surfaces of joints. Medicinal glucosamine usually comes from the shells of prawns and other crustaceans. You can buy a vegetarian version, made from maize starch. (My sister takes this, because she has a bad reaction to the one based on sea creatures.)

Glucosamine itself is unstable, so more than half the human versions are sold as glucosamine hydrochloride, a stable form.
Glucosamine sulphate is found in in tablets and capsules - it’s only stable when combined with potassium or sodium chloride.
You need to read the label to see how much actual glucosamine is in a product that is sold as glucosamine sulphate potassium chloride complex.

Then they report on chondroitin sulphate, another natural body product. It's this that makes cartilage rubbery so that it can help with joint impact or movement. They say that chondroitin sulphate mostly comes from tracheas of slaughtered cattle, pigs’ ears and snouts, or shark cartilage.

The report goes on to say that there is some evidence - but not strong evidence - that chondroitin sulphate helps relieve pain and improve joint function. They say:

There’s also a possibility that it provides an additional benefit when glucosamine and chondroitin are taken in combination

Regarding its safety, there were three provisos: one, as I mentioned, people (or dogs, I assume) who react badly to seafood should take care; two, long-term use could make an existing diabetes condition worse; three, those on blood-thinning medication need to take care.

The article ends with some advice that I think is valuable. The best thing to do is take regular exercise, lose weight and try targeted exercises.

I had a look at the product we feed to Penny, It has glucosamine but doesn't say what it's made from or how much of it there is per milligram. It has chondroitin sulfate that comes from 'socially responsible sources', not shark cartilage - now I'm starting to wonder what those sources might be! Finally, it has green lipped mussel powder. The Choice article mentions this as an alternative treatment that has not been proved conclusively to work.

It's all rather confusing for the average dog owner... but I think we'll keep using it for the present. However, I don't overlook the fact that the product I use is incredibly expensive. I'm hoping that it's a case of 'you get what you pay for.'