Cosequin Side Effects

Cosequin is a brand name veterinary joint supplement product that contains glucosamine and chondroitin. A number of different commercial preparations are available for cats, dogs, even horses. The product has been shown to be helpful in relieving joint pain that's often associated with arthritis. Although the various blends of Cosequin have been shown to be quite safe, there are some potentially minor side effects.


According to the manufacturer, most of the side effects that are associated with the use of Cosequin are gastrointestinal. Some animals may experience vomiting when first given this product. Combining Cosequin with a small amount of food may help alleviate this potential issue.

Stomach Irritation

A certain amount of gastrointestinal pain or discomfort could occur in some animals when using this supplement. Again, consider giving your pet Cosequin with a meal, or perhaps after finishing a meal, to help avoid these particular side effects.


Diarrhea associated with Cosequin use may be the result of administering too large of a dose of the product to your pet. Consider sprinkling smaller amounts of product capsules in your pet’s meals. If these symptoms persist, consult your veterinarian for further instructions regarding proper dosage.

Blood Thinning

Chondroitin is known to have blood-thinning properties, a potentially unwanted side effect that's associated with Cosequin use 1. There may be some risks associated with combining Cosequin and other prescription drugs, particularly those of an inflammatory nature. Additionally, due to Cosequin’s potential for thinning an animal’s blood, it's recommended that your pet discontinue its use before any scheduled surgeries or related medical procedures.

Allergic Reactions

If your pet has exhibited any previous allergic reactions to either glucosamine or chondroitin-related products, Cosequin may not be appropriate for use. Note that Cosequin blends are not prescription medications but are considered supplements or “nutraceuticals." So these products are not regulated by the Food and Drug Administration in the same manner as prescribed veterinary drugs may be. Monitor your pets closely when first giving them these products, and report any concerns to your veterinarian.