Hello, Thanks for writing in. Omega fatty acids tend to be very safe for dogs. There really haven't been any studies that determine the dose recommendations of omega fatty acids in dogs. Neither has there been a study that determines how high of a dose is too high. I have never really seen any side effects from these medications. The only real side effect that I would worry about it developing pancreatitis. I have never really seen it happened and would probably be more concerned with dogs that are already prone to pancreatitis. They also add calories to the diet as well, so you don't want them to get overweight. I usually recommend giving a brand made for dogs. The problem with human formulations is that you may not get good absorption of the fatty acids from the intestinal tract. The dog formulations are made so that dogs absorb them better. In general, you want a ratio of 10:1 to 15:1 omega 6 to omega 3 in the medication to get the best results. I have included a website that will give you a lot more information, including the amount of milligrams of each of these in various veterinary formulations. As you can see, it can vary greatly. Please let me know if you have any other questions. Hope this helps.