How Quickly Does Glucosamine Work in Dogs?

Glucosamine might help your dog get back into action, but it could take a while.
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If your aging dog isn't as active as he once was, showing signs of aching joints, glucosamine supplementation might put the spring back in his step. Unlike some prescription veterinary medications, it's not fast-acting. It might take a month or more before you notice any difference in his mobility. Consult your vet before giving your pet any new over-the-counter supplements or nutraceuticals.


As your dog ages, the cartilage in his joints starts wearing down. Cartilage acts as a shock absorber, so as it deteriorates and becomes less cushioning, movements become more painful. Eventually, cartilage wears down enough so that bone hits bone, resulting in osteoarthritis. While your vet has various medications available to treat arthritis pain, some have unpleasant side effects. Glucosamine helps build cartilage, is usually well-tolerated and can be used long-term. It can be given to dogs before they begin showing the telltale signs of arthritis and delay the onset.


Glucosamine consists of glutamine and glucose, an amino acid and a sugar. The body naturally produces glucosamine to aid in cartilage building but, as the body ages and cartilage wears, the amount the body produces might become insufficient. Glucosamine helps form the lubricants necessary to keep joints supple. While it can help rebuild damaged cartilage, it can't repair cartilage tears, scar tissue and other problems beyond normal wear and tear. Synthetic glucosamine is derived from crustacean shells. Commercial products often mix glucosamine with other nutraceuticals for added benefit, including chondroitin sulfate and methyl-sufonyl-methane or MSM.


While you can purchase glucosamine supplements for dogs over the counter, it's best to have your vet recommend a specific brand or write a prescription for it. That way, you know you are giving your dog a quality product with the amount specified on the label corresponding with the actual amount in the powder, liquid or tablet. Depending on the type of product, you can mix glucosamine in your dog's food or wrap a tablet in a piece of cheese or meat. Once you start daily administration, the waiting period begins. While glucosamine does appear to help many dogs, it doesn't have an effect in others. You might see results in as little as two weeks, but wait at least two months before deciding it's not helping your pet.


The answer to whether glucosamine actually works varies depending on who you ask. According to Veterinary Practice News, some vets aren't sure of glucosamine's benefits but prefer to "err on the side of hope" because of the relatively safe nature of the supplement. However, glucosamine might not be appropriate for dogs diagnosed with diabetes mellitus or suffering from bleeding disorders.

Fast Action

If you're looking for something that can relieve your dog's arthritis pain more quickly, your vet can prescribe non-steroidal anti-inflammatories. Never give your dog NSAIDs designed for humans. While these drugs work fast, they can also cause bleeding issues, ulcers and kidney and liver issues. If your dog's joints are particularly inflamed, steroids might help him. However, steroids can cause additional joint breakdown, according to the website PetMD.