What are the side effects of Glucosamine Chondroitin for dogs?

We hope you love the products we recommend and just so you know that as an Amazon Associate, we may earn from qualifying purchases.

Like humans, aging dogs may also develop joint health problems. They may start finding it difficult moving around and even have joint pain, which is why it’s a problem that shouldn’t be ignored. This is why veterinarians around the world prescribe supplements containing glucosamine chondroitin for dogs detected to be suffering from osteoarthritis.

In fact, glucosamine chondroitin is a leading supplement prescribed to treat canine arthritis. It’s also added to dog foods for health purposes to not only help with canine arthritis and joint problems but also as a preventive measure. It’s also possible to add the supplement to dog treats and other pet edibles.

What is Glucosamine and Chondroitin?

Glucosamine supplements for dogs are usually chemically synthesised or made from the hard polysaccharide shells of different crustaceans. However, chondroitin supplements for pets and dogs typically come from the cartilage of cattle or chicken. Some supplements are made using the cartilage of some sea animals like whales.

Glucosamine is a natural compound of amino acids and sugar which is produced in the cartilage. The body uses it to generate glycosaminoglycans, which improves the cartilage’s smoothness and helps it absorb shock better. It is the cartilage in joints that prevent bones that meet at the joint from causing pain and damage by repeatedly touching each other.

Chondroitin or chondroitin sulphate is sulphated glycosaminoglycan found in the cartilage of not only dogs but also humans and other animals. It not only helps in hydrating the cartilage and keeping it healthy but also controls enzymes at the joint from damaging the cartilage.

This is the reason why glucosamine and chondroitin are prescribed together to treat dog arthritis and other joint related problems. Besides, as some animals tend to metabolise glucosamine or chondroitin differently, veterinarians tend to prescribe both of them to get best arthritic pain and symptomatic relief. Whether prescribed separately or together, they both play an essential part in treating arthritis symptoms in humans, cats and dogs.


As mentioned above, glucosamine and chondroitin are especially useful and helpful at reducing the pain and joint stiffness associated with arthritis or osteoarthritis. Glucosamine helps by slowing down the cartilage degeneration process by providing the cartilage with building blocks that help synthesise new cartilage to treat canine arthritis consequently.

Chondroitin sulphate helps by improving joint elasticity, protecting the joints from cartilage-destroying enzymes and increases the joints resilience to compression.

Side Effects

Glucosamine and chondroitin supplements are relatively safe and don’t have much serious side effects. In fact, it’s scarce that you hear about dogs suffering from severe side effects.

Though the supplements don’t interact with most other drugs and vitamins, it’s always better and safer if you consult with your veterinarian first if your dog is taking medications.

Some of the minor side effects you can expect from glucosamine and chondroitin are:

Gastrointestinal problems

Vomiting and abnormal faeces like diarrhoea or constipation are the most common side effects associated with glucosamine supplements for dogs. If your dog starts vomiting or gets diarrhoea, its best first to decrease amount of the supplement you give, and try giving the supplements with food.


Your dog may suffer from allergic reactions if they are allergic to shellfish. These reactions may be mild where your dog may chew at his feet or maybe severe where your dog goes into anaphylactic shock, which requires immediate veterinarian treatment. In case your dog is allergic to shellfish, its better shifting to glucosamine dog supplements made from corn or other plant products.

Blood-thinning effects

Chondroitin is a blood thinner and may interact with any medication your dog is taking or may aggravate some medical problems. Stop giving the supplement to your dog if he’s scheduled for a dental or surgical procedure. Chondroitin’s blood thinning property can lead to severe and even life-threatening complications in your dog if consumed before surgery.

Affects blood sugar levels

It’s crucial that you regularly check your dog’s blood sugar levels if your dog has diabetes, and your vet recommends giving glucosamine and chondroitin. This is because glucosamine can affect some dogs’ resistance to insulin.

Interaction with painkillers

While glucosamine and chondroitin are individually harmless, it is especially dangerous if combined with a non-steroidal anti-inflammatory painkiller drug. So if you are giving your dog painkillers for arthritic pain relief, stop it immediately upon starting these supplements.

There’s nothing much to worry if your dog exhibits any of these side effects as they are all mild problems that are easily treated. Reducing the dosage of glucosamine usually helps control and stop the side effects.

Sometimes dogs starting glucosamine treatment require a higher dosage at first to reap its benefits. This sometimes triggers side effects or rather symptoms of over-supplementation which reduce later on when the dosage is reduced.

Lifetime arthritis treatment

Glucosamine and chondroitin don’t help treat arthritis; they are given to alleviate arthritic symptoms in your dog and make life less painful and more comfortable for them. It’s not possible to restore the bone and cartilage levels only through diet, and cartilage production tends to reduce as pets age.

So administering these supplements helps at slowing the speed of cartilage loss and also helps restore your dog’s glucosamine levels. In other words, you have to continue giving your dog these supplements for the rest of their lives for relief from arthritis pain.

Also, make sure you buy your supplements from reputed manufacturers. And make it a habit of consulting your veterinarian before giving any medications or supplements to your dogs. If it’s safe and advised by your veterinarian, glucosamine and chondroitin can help make life more comfortable for your pets.

And as you never know when arthritis may set in, do keep watching your dog if he starts to show any arthritis symptoms like stiff joints. If you notice any symptoms, you can always consult with your veterinarian about your apprehensions at your yearly checkups about the best time to start giving your dog glucosamine and chondroitin supplements.


We will be happy to hear your thoughts

Leave a reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.