• Open Access

Potential Adverse Effects of Omega-3 Fatty Acids in Dogs and Cats


Corresponding author: Dr. Catherine E. Lenox, Gulf Coast Veterinary Specialists, 1111 West Loop South Suite 140, Houston, TX 77027; e-mail: drlenox@gcvs.com.


Fish oil omega-3 fatty acids, mainly eicosapentaenoic acid and docosahexaenoic acid, are used in the management of several diseases in companion animal medicine, many of which are inflammatory in nature. This review describes metabolic differences among omega-3 fatty acids and outlines potential adverse effects that may occur with their supplementation in dogs and cats with a special focus on omega-3 fatty acids from fish oil. Important potential adverse effects of omega-3 fatty acid supplementation include altered platelet function, gastrointestinal adverse effects, detrimental effects on wound healing, lipid peroxidation, potential for nutrient excess and toxin exposure, weight gain, altered immune function, effects on glycemic control and insulin sensitivity, and nutrient-drug interactions.