Q I’ve heard many times that grapes and raisins are toxic to dogs, but how? Is it really dangerous for my dog if I feed her even one grape?
Dan Kurland
Boston, Massachusetts
Dear Mr. Kurland,
A One grape or raisin will not kill even a small dog, but a small amount of either fruit can prove lethal, which is why veterinarians suggest you don’t encourage your dog to expect them by offering one or two here and there when you’re taking some for yourself.
Ingestion of grapes and raisins (dried grapes) by dogs can lead to sudden kidney failure and an inability to produce urine. The exact mechanism for the toxicity is not well understood, but vomiting and diarrhea can begin within a few hours of eating either of those foods. Further symptoms include weakness and abdominal pain. Death can ensue within days.
Interestingly, not all dogs are affected. But why risk it and play Russian roulette with even a small amount?
Onions, garlic, and chives in any amount are not a good idea for dogs, either. They can cause a form of hemolytic anemia in dogs in which red blood cells die prematurely, keeping sufficient oxygen from getting to all the body’s tissues. The effect can be cumulative, so even if your dog doesn’t eat a lot of onions at any one time, the damage can occur with a build-up.
It doesn’t have to be raw onions, by the way (which even a dog probably wouldn’t eat). Onion rings, the dehydrated onions in prepared soups, onions sauteed with mushrooms or hidden with garlic in a spaghetti sauce — all of these can make dogs sick. Since onion and garlic are in so many dishes, think twice before putting your plate on the floor for your dog once you finish eating.