This popular joint supplement may help dogs with mobility struggles.
dog wearing harness on a walk; glucosamine for dogs
Credit: Jason Donnelly

Aching joints are often a part of getting older—for people and animals alike. Many of our dogs develop arthritis as they age, causing joint pain and limited mobility. Some dogs even inherit or acquire joint disorders, such as hip dysplasia, which may lead to arthritis at younger ages.

If you have a dog with joint pain, your vet might recommend a joint supplement like glucosamine to help ease discomfort and slow the progression of joint destruction. My own senior pup loves her daily glucosamine chew, and I can tell it makes a difference. Here's what to know about glucosamine for dogs.

What Is Glucosamine?

Glucosamine is a compound that naturally occurs in the body. It plays a role in developing cartilage, ligaments, tendons, and joint fluid. Cartilage helps protect and cushion the joints to avoid bone-on-bone contact. But degenerative joint diseases such as osteoarthritis cause joint cartilage to deteriorate, leading to pain and inflammation.

Glucosamine is available as a supplement to support joint health. It's usually paired with chondroitin, a natural compound found in cartilage and connective tissue.

What Is Glucosamine Used for in Dogs?

Your veterinarian may recommend glucosamine to support joint health, especially if your dog is aging or has a degenerative joint condition such as arthritis.

"Glucosamine is one of the fundamental building blocks of healthy cartilage, so the proposed benefit is that supplementation with glucosamine will help prevent cartilage breakdown from wear and tear and injuries," says Jo Myers, DVM and Veterinarian Expert at JustAnswer. She says that it might even help repair damaged or worn cartilage.

"Scientific studies provide conflicting results on these claims. There is no shortage of studies to show glucosamine supplementation doesn't help at all," Myers explains. "There are also a few good studies that show it has some promise, although that's more likely to be true for prevention rather than repair."

There are other possible uses for glucosamine in dogs. "Glucosamine is also a building block for other types of connective tissue that are found all over the body, including in the lining of the bladder," says Myers. "Scientific studies suggest that glucosamine is absorbed from the digestive tract and naturally seeks out connective tissue as a destination." Theoretically, your vet might recommend glucosamine to support bladder health in addition to joint health.

Is glucosamine right for your dog? Maybe. "These supplements are safe. The worst thing they'll do is be ineffective, so it doesn't hurt to try," explains Myers.

How to Choose Glucosamine Supplements for Dogs

Glucosamine for dogs is often available as a chewable treat. Common brand names include Dasuquin and Cosequin, but there are dozens more on the market. For my own dog, I chose Dasuquin Advanced because it's backed by science and preferred by many vets.

Some joint supplements only contain glucosamine and chondroitin while others include additional joint-supporting ingredients like methylsulfonylmethane (MSM). All these choices can make it difficult for pet parents to select a product.

"Glucosamine is a hot buzzword and marketing departments love to put it on labels for just about everything: food, treats, chews, supplements," Myers explains. "The supplement industry is not regulated, so many products on the market don't contain what they claim to."

Fortunately, your veterinarian can help. "Get a recommendation from a veterinarian since our training helps us find and accurately review the scientific literature on a product," Myers advises. She recommends selecting a product with independent studies that back up the label's claims about the quality and quantity of the active ingredients.

How to Give Glucosamine to Dogs

Glucosamine supplements can typically be given according to the label recommendations, but you should ultimately follow your vet's instructions for dosing. The recommended dose is typically higher for the first six to eight weeks (called a loading dose), then dogs remain on a lower maintenance dose long-term. Many pet parents simply add the flavored chews to the food bowl or offer them as a special treat between meals.

When starting glucosamine supplements for your dog, Myers says it's important to try it for at least two months. "There's a loading period before a glucosamine supplement will achieve its maximum effect," she explains. "Don't assume it's not working if you don't see any benefit prior to that time." 

After about two months, if you're not sure if glucosamine is actually helping your dog, Myers says you can stop and watch to see if your dog seems worse. "If he does, chances are good it was helping," she says.

Glucosamine Tips for Pet Parents

Glucosamine is not a cure-all or miracle drug, but it may help your dog. Myers recommends pet parents start glucosamine early—even before the signs of joint disease appear. "It's more likely to be beneficial for preventing wear and tear on joints than for repairing damaged, painful, or worn joints," she explains. 

It's important for pet parents to understand that glucosamine will not reverse joint damage. "Osteoarthritis (degenerative joint disease) is an ongoing process regardless of how it's treated," Myers says. "Symptoms are expected to grow worse over time even with an aggressive management plan." 

Beyond glucosamine, Myers stresses the importance of focusing on other aspects of arthritis management that you can control and that have a significant impact on joint health. "It's not a substitute for more important arthritis management strategies like weight management and regular exercise."

Glucosamine Risks

The good news is that most dogs tolerate glucosamine well (including when it's paired with chondroitin). "Glucosamine supplements are expected to be safe for dogs," Myers says. But while glucosamine itself is safe, she warns that some joint supplements contain manganese. "This can be dangerous when ingested in large amounts, particularly by smaller dogs." 

What happens if your dog eats a whole bag of delicious glucosamine chews? "In most cases, the worst result is some temporary GI upset," says Myers. However, it's best to contact your vet for advice if your dog eats an excessive amount of glucosamine. They can offer supportive care and symptom relief while your dog recovers.