Why Grapes (Sometimes) Kill Dogs

When I was a kid, I used to feed grapes to my black Lab and best buddy, George. Grape tossing was a trick, actually. I’d get George to sit, and I’d toss him a grape, which he’d catch in his mouth. Then I’d take a step back, and toss him another grape. Until I was twenty feet away, throwing grapes across the kitchen into his snapping mouth. (My mom wasn’t a big fan.)

You can imagine my shock when I got older and found out that grapes have been known to kill dogs. Was George invincible? Maybe a little bit. He got hit by a painter’s van one time and was none worse for the wear. But it would be more accurate to say that George was just a very, very lucky dog.

In one case, 4 or 5 grapes proved fatal to an 18-pound dog. As George was about 90 pounds, one could expect him to at least show some symptoms after eating 30 grapes, but instead, he was completely fine.

That’s Totally Idiosyncratic!

The reason why George wasn’t harmed is because grape toxicity is “idiosyncratic”, which means some dogs are affected and some aren’t. Unfortunately, we can’t identify which dogs will be affected. For this reason, it’s important to avoid feeding grapes, or their shriveled alter-ego, the raisin, to your beloved furry friend.

In dogs that are affected, grapes cause kidney failure. Early symptoms of toxicity can include vomiting, diarrhea, low energy, loss of appetite, trembling, and abdominal pain.

If you’re dog grabs some grapes, or gets into those oatmeal raisin cookies, then seek immediate veterinary care. Early intervention will increase odds of survival.

And if you’re looking for a good party trick, consider the tennis ball instead.